Edit....
It's the same thing as the eyetoy, check out the eyepet trailer on YouTube from Sony e3 2008. Natal is a total ripoff of eyetoy tech no denying it, you can scan items, it will track your movements, heat sigs, everything natal does eyetoy have already done. I'm not pulling this out my ass either, check out the demos of eyetoy and eyetoy2 on YouTube....... Read about it on wiki... Microsoft is late when it comes to this, I give them no credit for innovation on Natal because it was already availble on the playststion.
... and to all the posters saying that eyetoy was never supported check out the eyetoy section of the PSN store, everythin MS showed on the Natal is availble right now on the PSN and they have been availble for over a year now, not to mention the free app that comes with the eyetoy 2.