Casio announced a new keyboard that teaches you to play on your TV.

The Casio LK-202TV not only shows keyboard lessons on the TV but also features Karaoke.
The new 61 keys Casio music instrument also includes the light-up keys to help you learn quicker. Measurements are 944× depth 378× height 133mm.
The Casio LK-202TV will sell for 39,900 yen (~$348) in Japan starting September.
More details in this Casio press-release (Japanese). Find deals on Casio Keyboards.