I don't think Windows is done because there's always going to be a market for cheap(er) laptops and desktops. My girlfriend is a teacher. She can't afford a Mac. She doesn't want a Chromebook because she spends time in locations with no internet connection. She'll be buying a Windows machine for THOSE reasons.

Someone could absolutely disrupt Microsoft in the low-price market (and who knows, Chromebook might get there) but we're not going to see everyone switch to Macs just because the new Windows isn't great.