I used it for a few days, yet had to revert due to the laptop crashing in games (randomly turning black as in off). Alt-tab was also very slow when running games. Windows 7 never felt snappier afterwards.
Here's my experience http://gamrconnect.vgchartz.com/thread.php?id=210055
The best feature was the quick revert back to Windows 7. The laptop has been running a lot quieter again as well.