I see the Windows franchise beginning to sink at this point, as well as MS. This move seems good on paper, but the paradigm is changing and the windows brand that has been established for literally decades is going to have to undergo a phenomenal shift in order to be accepted on anything but a desktop OS. Not to mention that there are HUGE technical hurdles to overcome with this transition, as well as entry into a competitive space with major players already firmly entrenched and gobbling up new users at a record pace.

I don't see it being a total fail, this move simply stinks of let's-lean-on-our-established-brand-to-remain-relevant. I can't see MS taking a leading position in this new world of computing -- not even second place. Remember, with an architecture change, legacy application support will vanish, and the new Windows will have to start from scratch with no apps with competition that has tons. AFAICT, legacy support and brand recognition have kept customers locked into the Windows bubble.

Of course, if they pull a NaCl with some funky x86 to ARM translation, they may be able to surprise the critics (me). Though I'd be surprised if anyone could use a Win32 app on a low-res phone...

If they are just capitalizing on the trend of ARM slowly entering the High Performance Computing market, and still targeting desktops, then this is something different entirely. Interestingly, there is still relatively very little established desktop OS competition other than OSX and now Chrome OS. I have my doubts that this market will remain both the same and the same size.

But I'd bet that MS would still be beat (about the ears) in the server market by an army of Linux variants.