Re: Don't blame users for the UI
Whether they run 10 apps or hundreds of apps, I doubt that many existing Windows 7 or XP users welcome the need to learn the new incompatible Windows UI.
In embarking on the Windows 8 UI Microsoft was not aiming to make its install base of Windows users happier. It's obviously trying to grow into the huge and growing market of cell phone and tablet users where a small touch screen is required. MS wants to leverage its PC dominance as a competitive advantage in those new growth areas.
Historically, MS has done this with its office app UIs too. They didn't care much about impact to their existing users. Now they prioritize compatibility across widely diverse hardware platforms ("Windows everywhere") far above version compatibility on a given platform.