Multi-Touch Trackpad Gaming Demonstrated on MacBook
The developer describes it as tech demo and hasn't committed to releasing it. Illusion Labs is the same developer who demoed their iPhone games on a large multi-touch table in 2009.
All of Apple's notebooks now contain a multi-touch trackpad that could be used for such purposes. In fact, Apple's multi-touch trackpads can track up to 11 distinct multi-touch presses.