First let me say I really hate the Media Center interface!
Anyway the both GUis available when Windows is starting (this is when most people get coffee or go to the bathroom) if no touch sensitive hardware is detected the load the normal GUI. Both GUIs can make the same calls to the base OS to get stuff done.
Finally I find Windows 7 a set backward from Vista. All the W7 enhancements to Vista are minor details. W7 doesn't do anything Vista can't do with more cycles maybe.
Work for a company with 40-50,000 desktops/laptops still running XP IE6 with Firefox to fill the holes where EI6 no longer works. Comments were made at a large meeting that Windows 8 will be out before we see Windows 7 on a company PC.
Don't see W8 as being a big deal for PCs without touch support.
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