For me it's not so much a matter of usability per se, but about the business shenanigans which they seem to have learned from Apple: Metro-style apps can only be acquired (and therefor distributed) via the app store. It's a new hight in restricting the owner of a computer on which software he runs. Something they've started on Windows XP by limiting drivers, themes and whatnot to MS-signed-only variants.

I've installed Kubuntu on my SSD a week ago, and moved Windows 7 to an old HDD - just in case (and hey I've paid for it). Yeah it's not without glitches, but I sure as hell won't let a paid OS dictate what I may or may not install on my computer.

Nah, nobody complained that he had to move out from Vista to 7. Everybody knows that every other Windows version pretty much sucks it has become predictable. Just like 10% uses vista today, 10% will use 8 in 2020 in my opinion.

Yes. Yes it is. Not unless you have a trackpad or a touch screen. Then it's not as bad.

Win8 has become modernized by cleaning 7 and starting off with a fresh plate.

Its just that halfway through, Microsoft got confused and started adding things from Windows Phone Mango and Windows 7.

Later, they realized the problem but it was too late. Then they scrambled madly to try to remove some excesses from Win8 and try to make it ARM-compatible. Win(fa)RT was leaked.

If you could redux the UX, like in Android and Desktop Linux... no problem. But I think you're only allowed minor access to the UI side of things.