Microsoft has filed a patent for a system that could potentially use a camera to determine whether you're breaking its content-viewing rules or not. US Patent Application 20120278904 describes the ability to use a Kinect-like camera-enabled device for "continuously monitoring a number of users at a display device during the performance of [some] content," which basically means the camera would watch the faces of anyone watching a display showing licensed content (like a movie or a game), and then track those faces to see if the viewers had appropriately licensed it.
The patent lists a number of options for determining the validity of the possible viewers, including counting their number (as in, making sure only three people were able to see a movie), or actually identifying specific users (to make sure Julie isn't watching a movie that Mark was only licensed to see). The patent itself doesn't specifically mention Kinect, but it does mention the idea of a "gaming and media system" as well as "mobile devices" with the same capability.
Obviously, such a system would have some weaknesses (could you use a picture or a sculpture to spoof the camera?), and the patent states at the end that this is just one possible implementation of a setup like this. But Microsoft is apparently thinking about using Kinect's ability to recognize you for more than just throwing around spells and playing games. In the future, that camera may be used to figure out whether you're following the rules or not.
Microsoft files patent for device that enforces licenses through visual surveillance | Joystiq