Without actually being in front of it and taking time to see what you can do, Spore is hard to appreciate and understand. On paper, the idea sounds like a pipe-dream that could never become a game - and that's why it's all the more weird to play.
When you see how much work has gone into the creature creation, from evolution from primal sludge to interplanetary colonist, you see that Maxis have created a game that is plain special. You can choose to go from the very beginning in the Tide Pool, or jump into space instantly, creating a race and heading to the cosmos. Spore is your sandbox, with enough buckets and spades to keep you very, very busy.