I agree, I think Wii can handle it. I cant see why there would be any difference - other than graphically - keep in mind depending on your graphics card anyway you personally might not see much difference at all.
As Maleko pointed out before me the game is procedural. When you look at the galaxy stage with its huge universe its little more than a pretty picture until you interact with it, at which point the processing starts. I dont see any reason for it to be dumbed down - as far as I remember the only 'online' element to the game is having other peoples creatures download to your machine, each creature file is only a couple of Kb, so even with the very limited storage capacity of the Wii hundreds of life forms would take up very little space.
As Maleko pointed out before me the game is procedural. When you look at the galaxy stage with its huge universe its little more than a pretty picture until you interact with it, at which point the processing starts. I dont see any reason for it to be dumbed down - as far as I remember the only 'online' element to the game is having other peoples creatures download to your machine, each creature file is only a couple of Kb, so even with the very limited storage capacity of the Wii hundreds of life forms would take up very little space.