New upcoming patch updates for Civilization V have been posted by Greg "2K" Laabs on the 2K Forums. There's no ETA date known yet. Most interesting changes are that unit promotions and new civic choices can't be delayed anymore, maritime city states bonus has been decreased and an option to stop automated workers from removing existing features.

Click Read More for the full list.
Thanks to Jaybe for the heads up.


Updates:
AI

• Never use ranged units to provide flanking bonuses.
• Improve AI use of protected bombard attacks (melee in front, ranged in the rear).
• Worker priority adjustments (prioritize pillaged tiles, etc.).
• Further pathfinder optimization.

• Science building track adjustments (cost, specialist slots, GP Points, etc).
• Amount of damage caused during naval combat increased.
• Melee horse units combat value lowered, and now receive a penalty when attacking cities.
• Lowered bonuses received from Maritime city-states.
• Removed maintenance from defensive buildings.
• Multiple unit upgrade track adjustments. Most (but not all) units now have a full upgrade path from start to finish.
• Open terrain penalty lowered.
• Policies must be selected the turn they are earned.
• Promotions must be selected the turn they are earned. If it’s as a result of combat, then the beginning of the next turn.

• Added game option to disable automated workers from removing features.

• Worker AI improvements.
• Update to tactical AI pillaging code. Additionally, always check to make sure it’s not trying to pillage in an enemy dominance zone.
• AI victory emphasis improvements (more efficient end-game when focusing on Science and Diplo victories).
• AI should colonize other continents regularly.
• AI will emphasize production of an Ocean going explorer unit when the time comes.
• Adjust Napoleon to make him more likely to go for culture.
• More aggressive second wave expansion (mostly off shore) after initial empire building and consolidation has occurred.
• Optimization when finding routes (pathfinder improvement).
• Multiple tweaks and bug fixes.
• AI will now build ranged and mobile units more in line with the flavor settings.
• Multiple defensive AI tweaks.
• Never use ranged units to provide flanking bonuses.
• Improve AI use of protected bombard attacks (melee in front, ranged in the rear).
• Worker priority adjustments (prioritize pillaged tiles, etc.).
• Further pathfinder optimization.

• Cities heal more quickly.
• Only allow one upgrade per unit from a goody hut.
• Science building track adjustments (cost, specialist slots, GP Points, etc).
• Amount of damage caused during naval combat increased.
• Melee horse units combat value lowered, and now receive a penalty when attacking cities.
• Lowered bonuses received from Maritime city-states.
• Removed maintenance from defensive buildings.
• Multiple unit upgrade track adjustments. Most (but not all) units now have a full upgrade path from start to finish.
• Open terrain penalty lowered.
• Policies must be selected the turn they are earned.
• Promotions must be selected the turn they are earned. If it’s as a result of combat, then the beginning of the next turn.

• Tweaked the single-player score list to hide the civs of unmet ai players.
• Added game option to disable automated workers from removing features.

• AI's attitude towards you is now visible in the diplo screen and diplo drop-down.
• Added info tooltip for an AI leader's mood. Lists things that are making an AI player happy/upset.
• New diplo system: Declaration of Friendship (public declaration with diplomatic repercussions).
• New diplo system: Denounce (public declaration with diplomatic repercussions).
• New custom leader responses (Serious Expansion Warning, Aggressive Military, Luxury Exchange, Borders Exchange, Gift Request).

• Parent category counts now include counts of child categories.
• Selecting/deselecting a category now automatically selects/deselects it's children and its parent.
• Tweaked category name truncation to better fit names.
• Hide categories w/ no children and a count of 0.
• Added support for fallback languages (if mod is not translated, fall-back to English so text keys are not showing).

• Fixed save format which causes saves to increase the memory footprint of the game drastically when loading frequently over the course of the game.