Ok the pros and cons about the two systems. Pros for the PS3 is the pretty good graphics and the con would be it's going to taint the name and rep. for Halo. And for the wii the pro would be the hand controller and the cons would be the lack of graphics and it would still taint the name and rep. for Halo.
Getting back on topic, I think that the VR Halo is a bit of a fantasy.
By the time that those VR/MoCap game systems hit the mainstream I'm sure that some other FPS will take advantage of it, but Halo will probably be a distant memory. I've seen games in development for arcade centers and amusement parks that utilize this, but I'd have to say that the odds of Bungie every getting into that tiny little market are very slim.