I'm glad to see them go down this path. I've always said that the xbox thing was just a test bed for the technology and that it would someday be as common as the mouse on a PC. It may take a much smaller form when main stream on a PC, since it won't need to detect large "dance" movements, but instead be focused on more subtle gestures, primarily focused on the hands. Virtual keyboard anyone?
and though i principally agree with you, i understand MS invested a substantial amount of money to get this product mainstream, they would like to recuperate some of that expense, it kind of sux if other people are profiting from MS investment without contributing anything back to MS, it could result in MS losing large amounts of cash on Kinect while others are making a tidy profit from it