From IEEE Spectrum by Evan Ackerman [Link].

…we don’t have any actual specs on the new Kinect yet. Most of the details that we’ve got are from various (brief) hands-on demos, but here’s a rundown of the new stuff:

• “High-definition,” “high-fidelity” 3D vision. Obviously, the biggest deal for robotics is the improved 3D sensing. We’re not sure what “high-definition” means, exactly, but it’s definitely better, possibly 1080p 60fps better. The sensor itself operates based on time of flight (like a radar gun), making it at least three times more sensitive and lighting-independent. It can see the freakin’ buttons on your shirt from several feet away! This means better object recognition, better mapping, better everything that you depend on 3D data for.

• Active IR. Kinect can now see in the dark. IN THE DARK, PEOPLE!

• Skeletal tracking with joint rotation. When combined with a physics model, the sensor can estimate muscle movements and forces.

• Pulse detection (!). The sensor tracks color changes in your skin to determine your heartbeat.

• Emotion detection. In addition to tracking binary things like eyes and mouth open or close, Kinect also estimates your emotional state and whether or not you’re paying attention to it.

 A pretty amazing video demo from Wired: