Gamespy article
here.
I question how truly varied the interactivity and how 'smart' the ai's can be. Designing models on the fly is very very neat, even if it is limited and not as powerful as with 'real' tools.
Neverwinter nights made such a promise of user created content. Power over the game and ruleset wasn't so great.
Morrowind gave a very powerful editor, but its AI and in-game physical rules are still imited.
How much power will Spore really have? I see dynamic models. That's fun to a point, but how much will model changing really affect interactivity? What he proposes is powerful and fairly innovative, but still somewhat limited.
Mind you, I loved Simearth, and I like what he is proposing because I've played enjoyed simulators like that, but unless there's power and variance over how the creatures interact with each other, the 'game' portion feels fairly hollow. However, if different creature design greatly affects how they function, this might be a very complex game indeed.
I can't help but think of Black and White. Will the creatures really learn, grow, become their own personalities? Time will tell, but I somehow doubt establishing individual behaviour for that many creatres can be achieved on single home computers.