if you have got any (european) 720p TV channels that are choppy, this might be the reason :http://svn.mythtv.org/trac/ticket/7481#comment:4
I have problems with "EinsFestival HD" (sattelite - TechnoTrend S2-3200) and "DR HD" (cable). DR HD is only stuttering very lightly but einsFestival HD is unwatchable.
Recordings of DR HD is also not playable with Xine vdpau in beta2 (upgraded yesterday morning). Audio is stuttering - but video is slightly better.
Maybe the same fix can be used for xine ?