It's not really fair to compare Win8 to Win7. They are really designed for 2 different platforms. Win8 is really made for touchscreens (whether tablet/laptop hybrid/all-in-one or whatever else). It just doesn't run nearly as smooth on a 'regular' computer.
But Microsoft are pushing it pretty equally on regular computers also, which is why I think it's perfectly legitimate to compare them - and thus to completely slate whatever moron it was who decided that would be a good idea.
I haven't used it on a touchscreen, so can't really argue much on there - but from talking to people who have, it's not as good as the more regular offerings (Android / ios.)
I *have* used it on a Desktop though, and there it truly sucks. It feels like a bad combination between the old and the new interfaces - you get the impression they didn't have time to implement everything in metro (I know it's not technically called that anymore but I'll use that name anyway.) Some functions, like uninstalling stuff, just whisk you back to the old desktop view from metro, others go the other way around. I can understand that with legacy applications, but control panel stuff that's baked into windows? That's just half implemented.
Perhaps my biggest gripe though is that in the new interface, which Microsoft seem to be slanting to completely replace the old eventually, you can only have *one* window open at any one time. A rather famous usability expert noted that it should be renamed Microsoft "Window" for this reason. If you do some extensive Googling, you can discover how to have a second window active to the side (via some convoluted process Microsoft describes as intuitive) but the flexibility with the old desktop view of having multiple windows open in multiple places has just gone.
And that's where I'm going to stop, because for me that just makes the whole thing worthless. Windows 3.1 had better support for multiple windows than that, and I can't sensibly work without them. Yes, I can customise it to show the desktop view always but that isn't the point. If you only browse the web every so often, and perhaps use the built in apps, then perhaps it's ok. But for any sort of serious use, it's ridiculous. As far as I'm concerned, it's a half baked toy OS, an embarrassment that should never have been released.