The Wii is really just a novelty. I don't think it is that great. Sure they have a few great games, but that about it. The motion control shit just get annoying after a while. A friend of mine bought a Wii and for the first few weeks we thought it was amazing, but once the gimmick wore off, we were left with very little actual gaming substance. The Wii is the casual gamers console. It is the console to whip out when you have people and/or non-gaming friends over. It is Nintendo reaching the largest possible market while neglecting the die-hard gamer. The system itself is actually very weak. I have seen articles by game developers voicing their frustration at the extreme limitations of the Wii.
The PS3 has amazing capabilities that are in no way being utilized at the moment. The PS3 game library is laughable at the moment.
As of now, the 360 is the best console choice.
Of course, PC still wins.