Today during the reveal of the Xbox One, Microsoft unveiled the new Kinect. This is what it looks like, and how it improves on the original, as well as how it registers your body. It can even track your heartbeat.
These improvements are done with the purpose of putting the user at the center of the experience—with the Xbox One seemingly allowing players to control a ton of stuff with Kinect commands. Apparently, this is "ROCKET SCIENCE-LEVEL" stuff!
Finally, the Kinect is required for the Xbox One to function.