Have you actually used a touch screen on a Desktop? I'm not being snarky here; I genuinely believe that you should actively try to use a touch screen with a Win8 desktop before deciding one way or the other. I do it every day, and while it is not great for everything, there are some places where it is really nice.
For example, I love having a touch monitor when I'm reading a long Word document. Why hold a mouse and use the scroll wheel as I read a 35 page spec when I can sit there casually and flip through the document as I read? Or, if I have two hands on they keyboard typing and need to switch to another window, it can be nice to just tap the screen, rather than grab the mouse, navigate to the correct place on the screen and then click the button. Touch isn't perfect for everything, and I use the mouse plenty, but it's nice to have both. The key for me, however, was that I initially had to force myself to use the touch screen - I just wasn't used to it. Once I got in the habit of using it, however, I've found it has it's place and can be nice.
For example, I love having a touch monitor when I'm reading a long Word document. Why hold a mouse and use the scroll wheel as I read a 35 page spec when I can sit there casually and flip through the document as I read? Or, if I have two hands on they keyboard typing and need to switch to another window, it can be nice to just tap the screen, rather than grab the mouse, navigate to the correct place on the screen and then click the button. Touch isn't perfect for everything, and I use the mouse plenty, but it's nice to have both. The key for me, however, was that I initially had to force myself to use the touch screen - I just wasn't used to it. Once I got in the habit of using it, however, I've found it has it's place and can be nice.