I've updated the Poulsbo packages a bit over the last two days. Thanks to a suggestion from lkundrak the libdrm-poulsbo package is a lot cleaner now - it installs entirely to a subdirectory so it can co-exist happily with the main Fedora libdrm packages. I cleaned up a few other rough edges, but I made a major addition today. The repo now features libva and a build of mplayer with VAAPI support. What does that mean? Accelerated video playback on your Poulsbo, that's what it means! Ensure you have the repo enabled, do 'yum install mplayer-vaapi' (and if you already installed in the last two days, also update xpsb-glx), then try it:
mplayer-vaapi -vo vaapi -va vaapi somevideofile.avi
it can only play back the types of file it actually has acceleration support for - DivX / XviD, MPEG-2, H.264, WMV and a few others (see upstream for details) - if you try a video with a different codec it won't fall back to non-accelerated playback, it'll just fail. And it seems a bit patchy even on some files it supports. But when it works, it's awesome - it can play back 720p H264 on my Vaio P with only a smidgeon of frame dropping (compared to non-accelerated playback, which drops half the frames playing a 640x480 XviD).
I'm informed that the codec pack you can buy from Fluendo includes a gstreamer codec for VAAPI acceleration, which would allow any Gstreamer-based player to do accelerated playback. This isn't publicised in its description, though, and I'm not willing to shell out 30 Euros to find out. If someone else out there is, though, feel free. There's also a special version of RealPlayer with VAAPI support, but it's only available to OEMs, as far as I can tell.
Kudos to Gwenole Beauchesne, also ex-of Mandriva, who now works for Splitted Desktop Systems, who did the work to improve libva and patch mplayer to add support.