A new Civilization 5 patch has been announced by 2K Greg on 2K Games Forums. Here are the Civ5 patch notes and what 2K Greg says about:

Here's a fun surprise for you guys to read over the weekend: Patch notes for the upcoming "Fall Patch!"

There's no ETA for this patch at the moment other than "fall"

There are some popular requests in here that I bet will make some of you very happy.

And so without further ado:

Modding Addendum

The DLL source code will be released with the fall patch, allowing modders to compile modified DLLs for their Civilization V mods.

BUG FIXES

General

• Mod Browser - The "Get Mods" button is now hidden if the user has disabled the steam overlay.

Civilizations and Traits

• Ottoman naval upkeep is now fixed. Save games that were started before the fix will not be corrected.
• German UA and Oligarchy social policy now work together correctly.

City States

• Mercantile CS now only get a unique luxury for their first city (and not the cities they conquer). Unique luxury is removed upon capture (players can no longer get it by taking over a CS). Unique luxury is given back upon liberation.
• Prevent double counting of resources when an improvement is gifted to a minor civ, then the minor civ techs up to activate the improvement.

Diplomacy

• Research Agreement code was previously giving double-credit to research "overflows" (i.e. when you finished a tech and the extra research was being applied to the following tech). Now the credit toward a RA will be based on Science earned that turn.
• Corrected an issue that caused the AI to attempt coups too often, when chances of success were too low. Also implemented a new factor: Attempting a coup in a location where there is no defending spy (the current ally does not have a spy there) is >=2x as likely to work as it would if there was a spy there.
• Resurrecting a player will have both sides forget any denouncing that happened before resurrected.
• Don't treat player as a deal breaker just for going to war with a player again.

Exploits

• Do not let a player earn the 2 free techs from the Rationalism Finisher twice. Also removed the +1 Science from Libraries from that finisher.
• If you intentionally starve your city by reassigning all your citizens to be unemployed, you won't end up with more citizens than you have population.

Religion

• Fix Found Religion screen so you can't find out about civs you haven't met by mousing over the religion icons.
• Correct "Peace Loving" belief so it doesn't negate other happiness benefits from religion.
• Rebuild religious pressure in case it was corrupted in older save games.
• Clarify Interfaith Dialog so it mentions that Prophets earn you science too (not just missionaries).

Scenarios

• Removed notifications that appear at the beginning of the Fall of Rome and Mongol scenarios about lacking the proper strategic resources.

AI

• Dutch now will build farms before polders are available.
• Do not allow Carthaginian units to spawn on mountains.
• Do not allow Carthaginian Workers to end turns on mountains.
• AI will now build more workboats and will improve oil plots in the water.
• Automated workers that don't have anything to do will not consume all their movement.
• Allow rush built units to trigger the operation they were built for to proceed into Gather Units phase.
• Fixed an issue where automated workers evaluated danger incorrectly and consequently behaved incorrectly.
• Fixed an issue where citizen management focus on Production (and possibly others) could lead to starvation.
• Clicking on an unemployed citizen to set them back to work does not "unlock" locked citizen assignment.
• The logic to recommend Artist improvement placement now does not count plots where improvements can't be placed, e.g. oases.

Units

• Fix unit de-selection so the mini-map indicator clears.
• Better “Next Unit” selection. Previously, the camera would jump great distances to select the next unit that needs orders, when a closer unit was available.
• Unit cycling improvement: when a unit is promoted, do NOT cycle immediately off that unit.
• Change minimum area size for all naval units to 10 (from 20). That allows them to be built in the same cities as harbors, seaports (and great admirals) -- i.e. on any body of water not considered to be a "lake"
• Fix advanced promotions for melee naval ships.
• Restore missing Cover 2 promotion entries so it is available to units again.
• Fix a hang if a (melee) unit advanced across the world wrap seam after a combat.
• Correct Great Admiral AI placement bug that prevented it from selecting a valid coastal city of yours.
• Unit list now re-sorts itself correctly when a unit is promoted.
• Subs are no longer visible (all the time) in Hot Seat mode.
• Don't give GG points from Barbarian ranged attacks.
• Helicopters now take damage when ending their turn over mountains.
• Interception promotions now help the right unit (had previously been reversed).
• Evasion promotion helps the right unit (had previously been reversed).
• Two top-of-screen messages added to explain what is going on with intercepts (one for if the attacking air unit is eliminated, and another if he is just damaged).
• Fixed a unit movement issue that broke melee attacking from more than one hex away.
• Janissary heals 50 instead of 100 when killing enemy units.
• Supply promotion now heals 15 HP outside friendly territory; matching text (was 25 HP).
• Added a check to make sure that after a city is disbanded (ex. razed), the units remaining on the plot are allowed to be there. If not (ex. naval units), then they are moved to the nearest valid plot.
• Fix for barbarians that would not move the turn after they spawned.
• Have Great Engineer pick both the wonder and the city it needs to be built in (the bug was that the AI could repeatedly try to build a wonder in a city that it couldn't).

Optimization

• Many performance improvements, particularly in the renderer.
• Pathfinder fixes and optimization.

Text Bugs

• Fixed several text bugs.

Misc

• Fixed rare crashes that could occur depending on hardware.
• Only the “alive” civilization capitals are tested for majority religion in "We are family" achievement.
• Added missing Polish Dawn of Man audio.
• Advisors: Messages concerning your people being unhappy/livid now display correctly (a bug was causing this to fire at the wrong time).
• Economic Overview: Don't list diplomacy values as an expense and an income at the same time.
• Fix auto-scrolling between turns. If a user was scrolling when a turn ended, or when combat ended, it would occasionally get “stuck” and continue scrolling.
• Fix unit de-selection so the mini-map indicator clears.

BALANCE CHANGES

General

• Reduced Happiness a bit from Mercantile City States. You no longer get +1 bonus happiness going from Friends to Allies (since you already get the luxuries then). And eliminated the +1 Happiness entering Industrial era.
• Ballistics now requires Railroads. This will force the AI to get railroads before getting too deep in the tree.
• Pillaging tiles now awards +25 hit points to the pillaging unit.
• Tweaks to culture border growth:
  • Should get coastal resource tiles a bit sooner.
  • Should mildly steer towards tiles that are near unclaimed resources.
  • Should get resource tiles in rings 4 and 5 a bit sooner.
• Austrian UA balance changes:
  • Increase the cost of a City-State by at least the amount of gold you will get from scrapping their units.
  • Must be ally for 5 turns before you can undergo a diplomatic marriage with a City-State.
  • "Yoink!" achievement is now: "As Austria, acquire a City-State with 15 or more units through Diplomatic Marriage."

Religion

• Pilgrimage belief now gives +2 Faith per foreign city following this religion.
• Follower and Pantheon beliefs provide Local Happiness; Founder beliefs provide Global Happiness
• Faith output per city is now listed in the economic overview - general information panel. Note: Faith output per city is hidden if religion is disabled.
• AI: Buy Missionaries in city with Great Mosque as TOP priority (even over Holy City if different).
• Tall/Wide Religion Balance Change: Add Grand Temple (National Wonder).

Diplomacy and Espionage

• New peace deals. Now 9 AI levels instead of the previous 5 (so one new level added between each of the earlier ones). Peace levels are now:
  • 0: White Peace (give up nothing)
  • 1: Armistice (1/2 gold, 1/2 of max GPT)
  • 2: Settlement (all gold, max GPT)
  • 3: Back-down (all luxuries, all gold, max GPT, open borders)
  • 4: Submission (all resources, all gold, max GPT, open borders)
  • 5: Surrender (one city)
  • 6: Cession (1/4 city value, 1/2 gold)
  • 7: Capitulation (1/3 city value, all gold)
  • 8: Unconditional Surrender (all but capital, all gold)
• Peace deal code now prioritizes both cities that are close to winner's capital AND cities that were originally built by winning player (previously it was distance only).
• Reduced espionage notification spam. Will only be notified of election and coup activities if you have met them and (have a spy in the city or are friends with them or have a relationship with them that is above the resting point.)
• Added ability to liberate cities that are not owned by their founders or originally owned by the player. The player will receive a diplomacy bonus with the liberated player for liberating up to three cities. This liberation is not part of the "recalled to life" resurrection of a once annihilated civ. This functionality only runs if the city liberated is owned by a player that is alive. There are two ways to lose the diplomatic liberation bonus are:
  1. Declare war on someone you have liberated cities for. You have to be the first player declaring war. This does not count defensive pacts or someone you liberated declaring war on you.
  2. Capturing a city from someone you liberated. This case comes into play if A liberated a city of C's, then A and B have a defensive pact, C declares war on A and B, then A captures a city of C's. C will forget that A liberated any of their cities.
• The AI will now liberate cities and resurrect players. There are notifications when the AI resurrects players and cities. An AI will resurrect another (non-human) player when they are trying to win a diplomatic victory. An AI will return a city if the original owner of the city has a defensive pact with the player and they are both at war with the previous owner of the city, or, the AI and the original owner have a declaration of friendship and the AI is going for a diplomatic victory.
• Diplomacy: Peace treaty duration scales with game speed.
  • Quick: 10 turns
  • Normal: 10 turns
  • Epic: 15 turns
  • Marathon: 30 turns
• Diplomacy: Declaration of Friendships/Denouncements now scale with game speed.
  • Quick: 50
  • Normal: 50
  • Epic: 75
  • Marathon: 150
• Changed diplomatic globals:
  • The opinion thresholds (unforgivable/enemy/competitor/favorable/friend/ally) have been pushed farther apart. They were initally 50/30/10, now 80/40/15.
  • Diplomatic intrigue bonuses have been lowered by 1/2, from 20 to 10.
  • "Asked Stop Spying" penalty dropped from 20 to 10.
  • There are a number of changes to the duration of city-state interaction penalties, greatly reducing their duration.
• Diplomacy overview improvements. Now displays "your open borders/embassy", "their open borders/embassy", "shared open borders/embassy"
• With making deals, AIs will notify you when they're not willing to give enough on their side to make the deal work. This addresses some issues where you ask an AI to propose a deal and they say "we can't make a deal" and then you propose a lop-sided deal and they accept it. They will say "we aren't willing to give you enough to make this a fair trade."
• Other civs won't warn about expansion unless the player has founded a city in the last 10 turns.
• "We attacked your protected City-State" statements are now triggered by damage done (ex. killing a unit) rather than simply being at war. As a result, the statement should no longer be triggered by a quick succession of DoWs (such as those done automatically by a CS changing allies).
• The AI will no longer ask other players to join in a war when they are already involved in at least one.

Units

• Unit Balance Changes:
  • Drop Ironclad to 45 combat strength (from 50).
  • Remove +33% vs. Cities from Battleships.
  • Drop Gatling Guns to 30 Combat and Ranged Strength.
  • Make sure Air Ambush 2 and Air Targeting 2 work for fighters and bombers.
  • Carriers now get naval melee promotions instead of naval ranged.
  • Prize Ships Balance Change: 50% chance of converting ships with equal intrinsic combat strengths. Scales up and down (between 28% and 80%) based on relative intrinsic combat strengths of the two ships. Conversion chance if you do sink the opponent is shown in blue text on combat preview window.
  • AI attackers will now pillage.
• Promotion balance change: make the +200% vs. Cities promotion go away on upgrade.
• Promotions: Push back Air Logistics promotion for Fighters and Bombers so it requires Bombardment 3 (not 2) or Air Siege 3 (not 2).

AI

• AI adjustments to Wonder build priorities.
• Tactical AI Improvement: Spend more gold on defense. AI will now spend gold at their cities where tactical dominance is EVEN (before it had to be enemy-dominated). AI will now also spend money on naval and air units for defense in such cites (before it was only land units and defensive buildings).
• Changes to AI settling:
  • Expand the ring search.
  • Flatten the value of rings a bit so that tiles in the further rings are worth a bit more.
  • Make the default preferred spacing further for players not going for extreme expansion.
  • Lower the value of tiles a bit so that the AI is a bit pickier about settlements.
  • AI will try to reclaim lost settlers and builders.
  • AI will no longer wait forever for a settler escort.
  • Minor tweak to settlement location.
  • More aggressive offshore expansion.
• Do not give priority to bonus resources in rings 4 and 5 when deciding next tile to grow towards.
• Tweak to AI settle to reduce bonus of tiles in rings 4 and 5 if already owned.
• Small change to make Haile Selassie less keen to expand wide.
• AI will now consider annexing cities it has conquered.
• The AI will not consider annexing if it is trying to win a culture victory or their empire is currently unhappy.
• Increased happiness flavor for circus to match Colosseum.
• Tactical/Homeland AI Improvement: Do not heal if under enemy ranged fire (that is making you lose more HP per turn than you can heal).
• Allow AI to capture civilians more than 4 hexes from their cities.
• Have AI build its units for sneak attack at a slightly higher priority if at high difficulty levels.
• Have AI weight Biology a bit stronger especially if liking tanks and airplanes (unlocks oil).
• AI tweaks to help coastal based civs:
  • Change to settlement (cities beyond the first also prefer coast).
  • Buildings that help coastal Civs have flavors adjusted (they didn't take some rules changes into account).
  • Do not force high Naval civs to build a large navy (15+ ships) in the first 100 turns.
  • Make Dido deceptive (as historical).
• Tweaks to allow cities to make better use of extra tiles from previous change:
  • On average on extra worker or two will be built.
  • Slightly less prioritization of connecting up luxuries (still the highest priority).
  • Allow one tile islands to be settled (if they have a resource on them).
  • Slightly more prioritization of production tiles.
  • Builders will emphasize the capital so that it will always be a nicely developed city.
• City Governor AI:
  • Prevent focused city AIs from starving as much.
  • Make a wonder that has already been started in this city a higher priority.
  • Lower the value of food for the governor when you have a large surplus.

POLISH

UI

• Add in a UI overlay that shows which AI is processing its turn.
• In the detailed view of a mod in the mods browser, additional required mods will display their title if it has been provided instead of the ID of the mod.
• Add an “Exit to Main Menu” button to the player change screen in Hotseat.
• Added "Restart Game" option to game menu. This option lets you restart the game and generate a new map using your current pregame settings. It's only available at Turn 0.
• Advanced settings are now persisted across multiple single player games.
  • NOTE: This feature can be disabled by setting "PersistAdvancedSettings = 0" in Config.ini
• The top panel now displays the month of the year if the game speed is so slow that it actually matters.
• Messages about a player losing their capital and regaining it are now included in the replay log.
• Messages about a player being resurrected are now included in the replay log.
• Fixed an issue causing the replay graphs to be corrupted when a player was resurrected.
• Display currently active mods in the single player screen.
• Add a separate graphics option for enabling/disabling the GPU texture decode.
• Fractal added to the map short list and random map types.
• Garrison ring properly disappears when unit moves out of city.
• Resource icon stacking. At lower resolutions, the resource icons clip into the date display along the top. We now hide the part of the list that clips if it’s too long, and instead, the player can mouse-over the list to see all the resources.
• Better timing for pop-ups (finding ruins, etc.).
• Auto unit selection improvements:
  • On load, only cycle to the next unit if the currently selected unit is not ready for selection.
  • Swap the direction that the CycleRight and CycleLeft buttons move the selection in the cycle list.
  • When closing the city screen. Re-select the last unit that was selected.
  • If the player has auto-unit-cycling off, don't auto-select the unit that is blocking the end turn.
• Further refinement to pop-up reordering. Pop-ups should now "feel" correct each turn (in the right order, at the right time).
• Don't prompt the player when removing fallout. Just do it. The prompt incorrectly referred to the action as removing an “improvement”.

General

• Switch a number of Great Merchants to Great Admirals. Add Great General: Hannibal and Great Merchant: Jakob Fugger.
• Optimized overlay system (culture borders, etc.). This system is now making half the draw calls that it did before.
• Flavored all the civs for anti-air and air-carrier.
• Modding: Fix the hard-coded length of the promotions boolean array.
• Modding: Provide a way for Lua to query if the UI is in "Touch Screen" mode UI.IsTouchScreenEnabled().