You have to take in to account this is a developer preview to get people on board with Metro applications so much of what I don't like is probably already being addressed.
Its all very nice and fresh but is clearly aimed at touch devices, here lies the problem the interaction between the metro GUI and the 'old' explorer interface is a little hit and miss.
The lack of a start menu will affect the corporate market as I can't see organisations suddenly deploying touch devices to desktops just to take advantage of Metro applications.
There is some cool stuff though, the introduction of WinRT, the improvements to hibernation, a refresh build option to restore your PC to its original state and the security improvements are all pretty nice but I still can't but help but this this feels like another Windows ME. For the desktop at least, I think Windows 8 will be a success on touch devices, just not convinced about Windows 8 for everyone else.
Anyway, why not try it for yourself.
