I agree completely with #2 Kwaad, all signs of the game so far are pointing this way...
It just seems like flow, age of empires, galactic civilizations all rolled into one... and in the end most of the craft etc end up looking stupid anyway... it would be good if people could evolve 'human' like creatures this will be more 'main stream' I think. Not enough people are into alien like creatures and aliens for this to be successful enough I don't think.
I would prefer my race of creatures to be created for me by the game for the choices I make for them, from embrio form all the way to space creature rather than designing and controlling the 'look' of your own species... which is how I understand Spore to work... so if you make stupid decisions your race ends up being crap, that is what I want but I don't think this game will deliver that, if it does then SWEET and it'll kick arse.
That said I don't know if you can evolve humans, I haven't seen anything so far to suggest as such so I don't know.