Disagree. It will be the biggest investment in research Microsoft has placed in the mainstream market to date. Windows 8 is effectively a research project. Microsoft wants to know and understand how people will be using different modalities in their everyday work. Windows 8 will have huge issues, no doubt, but Microsoft will learn enormous amounts from it. Metro is a smart move - window chrome is unnecessary, and takes up more space than it should. Moving to a tighter and more relevant UI will prove beneficial in the long run. It will also test out some of the more tablet friendly interfaces, and most importantly Microsoft will learn how and why those fail in the desktop settings (and how to fix that). These are unknowns right now; Microsoft is going all in so they can discover them.

That said, Metro dashboard aside, it's a nice OS. If you stay in the desktop mode it's really just a faster and more stable version of windows 7. I've been using it as my primary OS for the last few months. The lack of a start menu will confuse people at first, but the keyboard driven execution of programs should be a welcomed change for many power users. There will certainly be a backlash from users, much like there was from Vista. Down the road though, I can see Windows 9 learning a ton from 8. That's where I see the true value of Windows 8.

Disclaimer: I work for Microsoft.