A signal from the TV tells each side of the glasses when to turn on and off, showing each eye slightly different images that create the sense of depth.
VOA: special.2010.01.26
Kinect Sesame Street TV side-steps the usual pitfalls for super-young players by balancing the game aspect of the experience with an ongoing TV show.
What makes this particularly fun is vTuner support, which allows for play back of 11, 000 radio and TV stations (primarily public access and other undesirables on the TVside), in addition to the increasingly standard FrameChannel service for photo sharing and RSS subscriptions.