Re: Adobe Flash 10.1 beta out!
Enable the Composite extension, to solve that gray-box issue - I've seen somebody posting about this somewhere, so this is probably a small bug, or sth.
You should be able to use vdpau vo and HW accelerated ffmpeg12vdpau,ffwmv3vdpau,ffvc1vdpau,ffh264vdpau codecs from there on. Edit your /etc/X11/xorg.conf file and change:
Option "Composite" "Disable"
Option "Composite" "Enable"