I can see two problems with touchscreen.
Firstly, and I think it's already been touched upon (excuse the pun), is the ergonomics of it. Sat here at my desktop, I am a comfortable 3 - 5 feet away from my monitor. To reach out and actually touch the screen is completely uncomfortable and quite impractical. Don't get me wrong, I'm no Luddite, and I will admit there may be workflow enhancements to be garnered from touchscreen technology, but for me that wouldn't encompass a vertical fixed screen. Rather, a portable, horizontal lap device.
Secondly, is the design and construction of touchscreen monitors more robust and resilient than current non-touch models? What I'm getting at, is whether continual tactile use will eventually degrade the surface of the monitor, both as a result of the physical impact and dragging, and of the effect of the oils and secretions laid down from one's fingers.
I've taken extremely good care of the current 24" HD and 22" screens I use, for a start because they weren't cheap and also because I want the
image quality to remain at an optimum. Taking the example mentioned in the OP, I can't wait to pay seven grand for a monitor and then start prodding it and smearing bodily fluids all over it.