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You mention the interface changes with Linux but you didn't mention that the user has the ability to choose alternative UIs that are closer to earlier versions of Gnome and KDE (MATE, Cinnamon, LXDE, Xfce, etc.) as well as the new UIs (Gnome 3.x, KDE 4.x, Unity). With Windows, you have three choices: Microsoft's way (Metro), remain with an earlier version of Windows, or 'take a hike'. I love Windows but am beginning to become frustrated that Microsoft refuses to listen to those that want the option to retain the Desktop UI with 'START' button (turning off Metro completely). I'm wondering just how bad their 'wake-up call' will be when Windows 8 Metro is released into the wild!