To say that Microsoft's Kinect could plausibly "spy" on its users, setting aside the amount of manpower, money, and time such a feat demands to so much as record the action of every individual partaking, is as crass as suggesting that the manufacturers of your webcam have been spying on your every move for as long as you've had it. Even though some conspiracy theorists had their time of day with Edward Snowden's recent drama, where he revealed several government internet surveillance programs, I highly, highly, highly doubt that a corporation would be interested in spending more resources than they did on logging your every move, not to mention the amount they would irrefutably be sued for if they ever are found doing so.