Heh. Surface has a full-size computer with cameras in it now. It's nothing like this.
Yah, to my understanding, surface needs t have cameras and sensors, and special lighting conditions etc.
BUT... this is nothing more then just a screen or surface, that can detect multiple touches at the same time.
Then along with that, is just an amazing OS/firmware that apple has written that uses the touches it detects, and well interprets them to do things.