That demo was really impressive.

[url]http://www.youtube.com/watch?v=gaQsXdKbUw8[/url]
This video is lagging, the live stream showed the motions were very accurate and fluid - 1:1 tracking with pixel precision.

I remember the Wii finally coming up with an add on of similar accuracy, what happend to that?

I hope the actually release titles utilizing the accuracy and precision of such controllers. A Sword and Shield PvP title - like the part of the demo - would be enough, add networking. I would buy a console just for that.