After a few days of use I can't say Windows has caused me any problems. I've had a few things to learn but it all seems to be hanging together.
One quirk I have noticed is that if you open an application, say Chrome, from the taskbar you get the normal window container, with close and minimize buttons. But if you open the same application from the Start screen you don't get a window container and have to drag the window to the bottom to close the application. This isn't a huge issue but it did confuse me at first.
Here is an article I picked up this morning that goes some way to explain why my laptop is now consuming significantly less power (be warned it's quite technical and a fairly long read)
http://arstechnica.com/information-t...-of-windows-8/