Very cool idea. Assuming no external keyboard, then this would not be ideal for lots of text input, since really good typists like the the tactile feel of the keys.... however lots of other things where text is secondary.... this could be an interesting twist.
For instance, for photographers, having a really big touch surface to work with could be a plus. Most of the "action" would happen on the horizontal surface, similar to what you do on a track pad/mouse pad, and ergonomically similar.
Hmm.... it would be worth mocking up... obviously you couldn't easily duplicate the touch-ness, but if you just duplicated the curve (perhaps drop the curve off the bottom of an iMac or other display) and see how it works ergonomically when the screen and the touchy part of the screen are actually in front of you.
Luck.