All this arguing about Tiles and Notification Systems is really missing the point.
Fact is, people (and by this I mean the sort of humans who
don't spend their time trolling various Tech blogs and forums) really don't buy Operating Systems or Computers because of things like that. they buy computers (and the OS that comes with them) because they need, or want, to do something that their current computing setup doesn't let them. And I think, based on this, that Microsoft 8 doesn't pass the "dog food" test.
Look at the commercials that Microsoft has been
playing recently: I think they reflect the reality that, for the past several years the PC market has become stagnant.
But does Microsoft really think that swapping the "Desktop" metaphor for a "Tiles" metaphor is going to persuade hundreds of millions of people to upgrade? I don't think so.
Granted, the worldwide PC business is so big that simple replacement cycles will mean that enough businesses and individuals will buy a new machine - loaded with Windows 8 - to make it a big seller. But its not going to do anything to change the momentum of the business, which has been towards smartphones and iPads (sorry) for their mobile and "lite" computing needs.
Microsoft held its "Build" conference to sell the idea of creating ARM-compatible versions of their Applications to Windows Developers. Which is fair enough. But the strategy of "Build It - and They Will Come" is far from a sure thing, especially in a world where consumers have lost interest in the PC, and a lean, whip-smart, and well financed Apple is setting the pace.