What about Lost Planet, Bioshock, Mass Effect, Battlestations: Midway, Command and Conquer 3, Forza 2, Too Human, Kingdom Under Fire? Some of these are released on the PC as well, but on consoles they're all exclusive to X360, and they're all third party games... There is quite some difference in developer/publisher support at this time.
I dunno about the Wii though... And there are quite a few third party multiplatform games too, that we'll see on PS3 and X360 at the same time. But exclusives are practically all from Sony for the first half of the year and there's only a few of them.