Game Trailers published a video review of Spore. I tried the game myself but I'm not really impressed, it doesn't live up too the hype and is dumbed down way too much.
I like the concept of building your own creature and watching how it evolves but Spore's gameplay is just too simplistic. The game's editor allows you to create billions of different creatures but most of those changes are just visual and don't have any impact on the gameplay.
For instance, you can choose between a handful of different legs in the creature builder but they all have the same specifications. You can alter the size of just about any aspect of your creatures but whether your creature is slim or fat, is a dwarf or a giant or has two or four legs doesn't give your creation any advantage or disadvantage at all. The same is true for the civilization stage, you can build a couple of building in your cities but it's all very dumbed down.
It might be a nice game for the casual (young) gamer but the more seasoned gamers may not get much out of it.