Ah, there’s the rub. For this to work, the new Windows must work “as expected.” What if it doesn’t? What if Redmond lays an egg and the new operating system is reminiscent of Windows ME or Vista? Will users be given the ability to roll back to their old OS as they could during the Vista brouhaha? And imagine the public relations nightmare if 10 turns out to be an utter fail. It could happen. This is Microsoft, after all.