One of the more anticipated titles showcased at this year's E3, Civilization V was shown off at 2K's booth. We managed to sneak in (via appointment) to catch our first glimpse of Civ V, and it looks very promising.
The team at Firaxis has made a lot of changes to the Civ formula, one of the largest being the switch to hexagonal tiles, rather than square, as in previous games. This lets the world itself look a little more natural, especially on coastal tiles. It also adds another element of strategy to attacking and defending, since there are now two extra angles to be attacked from. On that note, the "Stack of Doom" has been done away with. For players unfamiliar with this tactic, you are able to stack an unlimited amount of units on one tile, making attack and defence extremely difficult and drawn-out. In Civ V players are limited to one unit per tile.
Some other changes to the game include the AI itself. While some leaders are pre-disposed to a certain strategy (ie. Combat), if you keep pounding them down, they may switch to focus on a cultural victory rather than a conquest one. As well, the use of terrain as cover has been upgraded. The AI will naturally use hills and forests to defend and attack, using its bonuses to overcome your troops.
Civilization V will release with full Steamworks and DirectX 11 support in just one more turn - I mean, this September.