Been using windows 8 for a week. It's very different. The metro interface is so window-less but really works. For a developer preview it seems pretty good (Solid, no blue screens or hangs). The only thing I did not like was the sample clock HTML5 web application seemed very high on CPU usage and did not suspend. But its a developer preview so I can't complain. I think that Microsoft has learned a lot over last few years. Still not sold on Javascript/HTML5 but since Microsoft is pushing C++ (they've done some good integration with XMAL.)