That's actually the problem...
Apple made iOS from MacOS X, like Windows CE from Windows. More lately, they have been embellishing MacOS X on the desktop to make it more of a "home" for iOS users. But that's not the same as making it the same as iOS.
A desktop is not a phone or a tablet. There are deas from the tablet/phone that work on the desktop, but that's different that iOS on the desktop, and Apple knows it. Microsoft seems to be moving to unifiy the versions of Windows, and in a bad way. Sure, why not unify the kernel... there's no reason Windows Phone 7 needed to be this weird single processor anomoly. Most recent portable systems have the same CPU power, similar storage, and more RAM than desktops of a decade ago... when Win XP hit the desktop. And XP deep down wasn't that different than Windows 2000, which ran just dandy on much lesser machines.
It's the "API server" that makes the difference. Windows 7 has two of these, the Win32/64 API server (Windows apps), and the POSIX server (easy UNIX ports). Windows 8 adds another, WinRT, the API that Metro rides on. The Phone/Table OS, Microsoft's answer to iOS. This is the one that will only have applications for sale from the revamped Zune store, that'll run on tablets, is running on Phones. But they're no taking some good ideas from the tablet/phone and enhancing the desktop -- they're putting iOS on the desktop. And from the sound of it, forcing you to use it, despite the fact that the interface completely fails as a desktop UI.
Microsoft needs the consumers to adopt desktop Metro/WinRT, because they haven't found any other way to get users to buy into Windows mobile OSs. But they're just as likely to kill the desktop this way. This is one case in which they actually should copy Apple.