Is it so hard to imagine that in 5 years most people will have tablets that they dock into a larger monitor and use with gestures and dictation instead of mouse and keyboard?
Maybe for light work and consuming media (which is already what tablets are used for) but for heavyweight work a keyboard and mouse is going to be the interface of choice for a lot longer than 5 years. Do you think, for example, a Visual Studio developer is going to use gestures and dictation to write code, 5 years from now?
In any case, that's fine, that's why there's a tablet edition of Windows 8 - WinRT, and a separate phone-optimized version too. Having separate user interfaces optimized for different tasks is great. So why force the desktop edition to use the tablet interface? If they must bundle the tablet interface in with the desktop edition, why not make it optional, and just make the tablet interface the default on devices with a touchscreen?
To use a vehicular analogy: to keep up with the trend towards motorbike use and away from cars, Microsoft Automotive's latest model of car now has no steering wheel, pedals or seats. Instead it has handlebars, a throttle joystick, and forces you to lie in a prone position, but only when turning a corner.
I think I understand what they're trying to do by forcing the Metro launcher on desktop users, but I don't think they have fully grasped exactly what their bread-and-butter users think of that. It will hurt their reputation even more than the Vista debacle. It could even kill Metro altogether, and with it, Microsoft's plans for phones and tablets.
Its entirely possible that the mixture of mouse, keyboard, voice, touch, stylus with all the different forms of breaking off screens and keyboards is such an amazing computing experience that it becomes the future. Obviously disaster is more likely, but the vision here is rather bold and exciting.
Sure the vision of Metro is good, but the implementation of it on Windows 8 desktop, with the constant jarring between the familiar desktop and the Metro launcher/start menu, is going to send desktop Windows users mad. For most people the desktop Windows 8 Metro start menu is going to be the first time they've seen the Metro style, and so far it doesn't look like it works well there, not with the keyboard and mouse that most will be using it with.
My suspicion is that it will engender such a dislike for Metro that it will actually put people off Metro altogether - the exact opposite of what Microsoft are hoping will happen, and not good for WP8.
"If there isn't a population problem, why is the government putting cancer in the cigarettes?" -- the elder Steptoe, c. 1970