Yea, I think it's using the Infa Red, changes, and looking for a pulse (I guess in you neck?)
As xwan point it, it may not really work that well. But then, this time of flight stuff they are doing with Kinect 2 is rather impressive. Kinect 1 has been used to map caves, and all sorts of non gaming uses.
I think it both sounds cool and is a little bit creepy. I could see how they could use it on a game say, like Alan Wake, to keep making it hard for you by seeing if you are 'stressed enough' before opening a door, or letting you move onto a new level.
I wonder if it could also give alerts? My friend Glen had a heart attack after playing his new PS3 for 3 days. He was super excited and saved up for a long time. Then played for a long time.







