Ugh. Have you ever tried using a touch-sensitive screen? (they've been around for years).
I thought not....
If you like RSI, aching shoulders and greasy screens, that's the way to go
Seriously, though, for a touch screen to be comfy to use, it needs to be horizontal. Horizontal works fine for designers (viz the Wacom tablet that has an integrated display), but isn't too useful for other things - certainly for gaming, watching movies and general typing, the screen needs to be close to vertical.
My verdict - never gonna happen. I think what we _will_ see from the technology is a wider range of more versatile controllers/input devices. I can certainly see multi-touch benefiting those of us who use graphics tablets...
exactly, multi-touch mac/pc's will never be the standard, they will simply be another option of input (a popular one at that though)