Is metro really that polarizing?

Metro is obviously a huge change, a revolution. It also inspires "passion", as evidenced by the emergence of the MS fanboi "army". There are also other people who hate it with a passion.

It is safe to say that MS has tested people's reactions to it extensively and want to remain the dominant "force" in software field.

Based on that, and the unquestionable support by all the OEMs, is it safe to say that W8 will NOT fail? There are a lot of people who predict it doom, but I just don't see a possible way for this to happen.

What are the arguments for those doom-sayers? What should align to make W8 a flop, and how likely are those events/things to happen?

One scenario i can see is that apple enables licensing of osX and/or it's successor and that OEMs widely adopt it, which would bridge the price gap macs have right now. But that is highly unlikely. Are there any more reasonable scenarios?