Gnome and Microsoft know tablets are the new hotness, so they are forcing us to switch to a tablet optimized interfaces. One major problem, Most of us are not using it on tablets. Now that gnome has had its backlash and microsoft is getting their earful of leaving the default gui everyone likes alone, a task bar (with clock and quick launch), task manager, and app tray. We can get back to implementing new features and not messing with users experience in working.
Its like getting in a car, and the steering wheel and pedals are gone, first thing a person does in an accident will be stomp their foot on the floor pedal break, which will be missing. Muscle memory.
I will say, even Android is pushing its annoyance limits on newer versions, moving settings around where if your a long term android user you expect settings and buttons in one location and its moved. It can be a little annoying when you cant find something. Messing with peoples routine memory is annoying and actually infuriates people.