I haven't made up my mind on the Kinect being integrated with ME3. I think I'll wait to have a full opinion on it when the game comes out. I have a Kinect, and so far, everything I've played on it has run the gamut of being a short time gimmick to nice, fun experience.
Dance Central is still the best Kinect game in my mind, and if that part gets incorporated into ME3, then I'll definitely be taking my Shepards out on the dance floor.