At some point Kinect WILL be used in a Halo game, that is a fact but to what extent will it be used?
Before we jump to that, Halo could NEVER be Kinect only so forget about that.
What would the Kinect add to Halo or how would the Kinect be used in Halo?
With the Kinect, Master chiefs face WILL be revealed (It was you all along)
Hold the controller in your (left or right) hand and throw precision grenades WITH YOUR HAND! Perhaps we can even throw a little English on it?
Hold the controller in your (left or right) hand and melee for realz!
Swing your head for a quick turn around to avoid assassinations!
Zoom in with the sniper and follow targets with your finger for those epic head shots! (I just owned you with my finger!)
Hold the controller in your (left or right) hand and have you Spartan perform some of the following:
Raise the roof (both hands in the air, raise them up and down)
Oops (hand in front of mouth)
T-bag (FOR REAL)
Aerial assassination ( Jump off your couch maybe even do a flip or two)
Added your idea on how it will be used.