Lift your hands from the keyboard and put your fingertips on your screen.
Now hold them there for the next eight hours.
Doesn't take too long to come to the conclusion that touch-screen desktop computers are overrated.
Similarly, try speaking aloud everything that you type. Aside from privacy concerns (I really don't want the guy in the next cubicle knowing what I"m ordering from Amazon), voice is basically a command-line interface. And speaking with the clear enunciation and stilted, unnatural style that computer voice recognition requires puts a lot of strain on the old pipes.
And rumor has it they want to have a webcam ID login upon windows boot.
I can't wait to see all the tickets the IT department gets from people who can't log in because they're having a bad hair day.
I played with one of the HP iMac competitors at Best Buy. It had a touch screen. Talk about the most useless feature ever on a desktop.