New laptop multi-touch screen

Multi-touch is creating a lot of buzz lateley: Jeff Hann, Mitsubishi DiamondTouch, EON Touchlight, iPHone and Microsoft Surface. Now Microsoft is working on a new multi-touch adventure: multi-touch for your laptop. With some infrared sensors they transformed a normal laptop-screen into a multi-touch device. Not sure if you want to use this kind of interaction for all applications, but if this is a low cost solution, why not put this standard in tablet-pc’s and umpc’s?