When using fences in Win7 RC1 on my netbook, when a wallpaper is changed (and only after the wallpaper is changed), the contrast of the wallpaper is horrible. After reboot, the wallpaper will look fine, but if the wallpaper is changed again, the problem returns and cannot be corrected until reboot.
I have an intel 945 graphics chip, an atom processor, and 2gb of ram.