Yes, we will have irrigation, mines, roads, railroads, etc. Since the game goes out another 1000 years into the future, there will also be future improvements (maglev trains, for example). But we have changed the implementation.

We found that in Civ2 when you had discovered refrigeration and railroads that you ended up spending a good part of every turn micromanaging your settlers/engineers as they landscaped your territory. We've taken some steps to reduce this.

First off, your settlers will no longer be involved in tile improvements. We've done away with engineers, although there is a corresponding unit that you can build when you have the technology that will carry out terra-forming (turning swamps into grassland, etc.)

Secondly, tile improvements (roads, farms, etc) will be purchased on a macro level. You will earn a number of civic improvement points each turn depending on your wealth, production and government type.

To clear it up, here's an example:
The red Civilization earns ten civic improvement points at the beginning of its turn. Looking at the improvements interface, the player sees that farms cost 2 points and roads cost 1. He decides to spend 6 points on three farm tiles. The player then selects the tiles that he wishes to improve, and clicks on them. The farmland claims are laid down, and it is assumed that workers from the nearby towns are working to create the farmland. As in Civ2, farmland will take a few turns to complete.

Next, the player spends three points buying three road tiles. He selects where he wants them to go, and (unseen) work begins to build the roads.

The player can save unused points until the next turn.

Land improvements will be tied to technology advancement, and there will be different levels of improvement (like irrigation, refrigeration, etc.)

Please note that all numbers that I have used here are for example only. We are still playing with the cost of things as we balance the game out.