......but of course, when it comes to UIs, it's primarily a matter of taste. I can't seem to get on with iOS, but really like W7 and feel right at home. Other people feel the opposite. And I share your opinions of W8 if we were talking about on a desktop.
All modern UIs are designed to be a usable as possible, obviously, so there are probably no "bad" ones any more. We've got to the point where we are in a similar position to buying a car - almost any make will do the job you need, but most of us have a preference for Ford, GM, Jaguar, or whatever.
Microsoft have taken a risk and gone for what is probably the most radical UI currently available on portable computers. As with any radical product that's away from the mainstream, some will hate it, others will like it. I really like it, as I've said, but I've no idea whether it will be successful or not.
I think that whatever magic it is that makes some products successful and others bomb is still a bit of a mystery. Marketing has a lot to do with it, of course, but there's the capriciousness of the buying public that makes things pretty unpredictable in the end.
It will be interesting to see if anyone else speaks up in favour of the Modern UI.
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