Looks like something out of Minority Report.
Another one: http://gizmodo.com/gadgets/keyboards/laser-keyboard-getting-usb-update-still-hard-to-use-289427.php
My uncle used it and said it was way to slow and inaccurate, but the advantatage i guess is you could type on any surface, as long as it is reasonably flat.
The glass keyboard is basically a Microsoft "Surface" without the screen. Meaning you could point the camera at any glass surface and virtually use the other side as a typing surface. If you exclude the screen this means it might actually be possible to use curved glass as a typing material, but as a previous poster said, the key action is lacking and there is almost no audible sound.
But like all technologies they can find their own niches within the market. You could easily seen it being used in a market where it is messy and need a easy to clean surface or for waterproof computing in industrial areas.
