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That would've been an interesting use case for bridging the experience between tablet and traditional PC. Unfortunately what they've actually done is saddled the traditional PC with an overengineered interface full of metaphor shear in a misguided attempt to shoehorn all devices into a unified environment.
The simple fact MS is missing is that people whose computing needs are filled by tablets and mobile devices will just buy devices and tablets. They don't need their desktops to mimic those devices because, quite honestly, they don't need their desktops anymore at all in a lot cases.
The people who will still be buying desktops, who will always be out there contrary to what some crack smoking tech bloggers may think, will be doing so largely because tablets and such don't fit their needs. They don't want to be hampered by interfaces that were clearly not built around their use cases. They certainly don't want to waste time and energy relearning their workflow because some monkey thought it'd be a brilliant idea to try and force convergence along.