GameSpot has a preview of the fourth title in the Civilization series, Civ4. If you're a Civilization-head -- and my brother and I are both most certainly that -- you'll be interested in the unprecedented big changes proposed for the new game. Here's a taste:

The key thing to keep in mind that while the overall idea hasn't changed (you guide a civilization from the dawn of time to the near future, and you'll explore the world, found cities, research technologies, and compete against rival civilizations), the formula has been overhauled in a way that it hasn't been before. Johnson told us that they wanted to get rid of the things that have always not been fun in Civilization, such as having to constantly clean up pollution or battle corruption or things such as that. In their place are a slew of whole new gameplay features and ideas that have us excited about a Civ game like never before.

Religion added, the tech tree system completely overhauled, governments and culture redefined, new systems of leadership...sounds like a fun time.

There are screenshots, too, though they won't tell you much.

[via Slashdot, which also has previews of the new Mario title and We Love Katamari]