There's a fair number of 3rd party exclusives on the horizon, if only because the Wii tends toward playstyles that aren't compatible with other consoles. I don't think 3rd party vs 1st matters in this context, though. Exclusives are for drawing consumers to your platform, and I don't think they care who made the game as long as it's awesome.
A comparison of exclusives can be a little misleading, too, since there are many titles which come to both PS3 and 360 but not Wii, while you'd be hard pressed to find a title that's on PS3 and Wii, but not 360, for example.
"The worst part about these reviews is they are [subjective]--and their scores often depend on how drunk you got the media at a Street Fighter event." — Mona Hamilton, Capcom Senior VP of Marketing
*Image indefinitely borrowed from BrainBoxLtd without his consent.
