Win8 and touch works well for tablets - and I don't believe that anyone is arguing with that.
Where the disagreement seems to be focused is in whether or not there were compromises made for people using traditional desktop/laptop type of equipment and applications - i.e. the majority of business users.
For me, with a desktop and dual 24" screens, Win8 just doesn't work as well as Win7.
I am a long-time MS supporter, and I really tried to like it, but I ended up going back to Win7, for a whole host of issues, both major and trivial. After all, nobody is forcing me to use it, so why should I feel a need to compromise?
It's purely a personal issue, but as someone who has a disability that makes all physical movement very taxing, I notice even minor changes in UI efficiency. For me, a keyboard requires significantly more effort than a mouse, and touching a screen requires significantly more effort than a keyboard. All things considered, I found that Win8 required more effort to achieve the same result than did Win7.
I realise that most people would not even notice such issues, and that many people actually even prefer the new UI for a desktop/laptop environment, but nevertheless, I feel that these UI changes could have been made optional for desktop installations (with MS even imposing their preferred defaults) allowing users to choose not to use it where it is not suitable or desirable.
Unilateral, non-negotiable and "uncompromising" changes to the UI will always cause problems for some, and with such a large installation base, even a small %age is still a very large number of people. I struggle to see why there was a need to create such unnecessary agro.
For me, for a tablet? no argument, but for a desktop? no thanks.