It's silly to include the portables in that list. >_>
Anyway, I'd go with:
1. 360
2. Wii
3. PS3
Mostly because the PS3 doesn't have much going for it right now. I think it might be fair to say it's more powerful than the 360, but there aren't yet any really good exclusive games for it. GTA4 is going to have 360-only content, and MGS4 keeps getting delayed. Anyway, I don't like either of those games.
And though the PS3's internet stuff is free, it's hardly worth having compared to the 360's. Plus, Xbox Live is only $5 a month.
The Wii is fun, but I don't think it has the staying power that traditional consoles do. The motion-remote thing takes away a level of abstraction that makes significantly different control schemes on the same controller be able to work. In other words, the control system is new and fun, but too simple. There's only so much you can do.
As jits and others have said, though, PC > all. Though with the consoles (or at least the 360), you get much more processing power for your buck.