consumer vs producer
iPads, tablets and smart phones are fine if what you do is consume content. If you create content, then you need good input devices kind of like a keyboard and a mouse. Nobody has beat those yet. Yes, I have a 3-D mouse for CAD work and I love it.
I do a lot of photo and graphics work. I wouldn't mind having a Wacom Cintiq, but I don't want to be putting fingerprints and secret sauce all over my monitor. I would be cleaning a touch screen every five minutes so I would know if I had some sensor dust or if the monitor was funky. The two things that aren't covered under warranty are the battery and the screen. Go ahead, teach your 5 year old to poke at the screen, I dare you. It was bad enough when it was just a display; now add a touch sensor and see how much they bugger you for on repairs.
Apple has iOS for it's portable, non-laptop devices and an OS for laptops and desktops. M$ should consider the same route and not try to make them the same at the top level. A fondleslab and a desktop are going to be doing different jobs with just a little overlap. It's inane to try and force people into one mold for all of their computing. Corporates don't like radical change. Everybody takes too long to get back up to speed and the IT department racks up a huge amount of OT trying to service all of the issues with any new release (hint: bofh story line). M$ would be better off keeping the Start menu and having the option of other UI configurations. Some people will gravitate towards each, but the office will still function smoothly. Phase in, phase out.
My setup: MacPro 4xCPU running OSX 10.6.8 and in VMware, Windows XP and Ubuntu. I need to live in all three worlds and this is the best way I could find to keep the number of kb's, mice and monitors down to a livable number.