Its called Spore
Here's the Gamespot preview:
http://www.gamespot.com/pc/strategy/spore/index.html?q=spore
Although the Wiki article explains the concept better:
http://en.wikipedia.org/wiki/Spore_%28game%29
"Spore is, at first glance, an evolution game: the player molds and guides a single-celled species across many generations, until it becomes intelligent, at which point the player begins molding and guiding a society into a spacefaring civilization"
If this game is as thoroughly developed as the Sims was, it should be very exciting.
P.S. Its quite possible this game will be published by EA. If you don't like that or don't like EA, feel free to discuss that elsewhere.