Re: Plenty of hardware available.
Motion controls for games probably is a novelty, or at least more of a very kid-centric sort of toy. But Kinect development has gone way beyond games at this point. There are business and medical apps that use that motion sensor package and MS is hoping to build on that.
Of COURSE they did this to ultimately increase their bottom line. Helloooo...corporation? You know, just like Apple, IBM, all the rest?