However this isn't a test of precision. The motion required is large displacement of the hands that'd be easy to track with a standard camera if the contrast if high enough.
Well, we are a tech board! Plussome of us have already discussed much of the potential with other devices, like PSEye. I was a huge believer in EyeToy's potential. Back in the day, the inclusion of EyeToy2 as standard with every PS3 was a matter of some enthusiasm with me, and I preached all the lovely possibilities. Here we are, years later, with very little to show for it. A lot on offer in these Natal demos has been possible for years, maybe not to the same scale, but certainly to a good standard. It appears to have awakened the interst in some parties who missed the EyeToy scene, which is good. The more momentum here, the better! To some of us though, it's not terribly new, save a few aspects like Molyneux's choice of interactions.