The device itself (as a standalone unit) has been around for a few years now, and was the center of some really weird controversy over patents and stolen ideas...

Those that did get their hands on one were not impressed:

The projected image is too dark
Tapping away on your desk really hurts the fingers after 10 minutes
It isn't very accurate

The technology behind the system sure has potential, but it will take several years to reach its full potential...