Releasing a driver with working H.264 acceleration has been another story however - Until now. CATALYST 5.13 is the first ATI driver to support hardware assisted H.264 playback for all of the Radeon X1000 series. The only caveat of this support is that the level of High Definition playback your system will be capable of running smoothly will be largely dependant on what member of the Radeon X1000 series is sat inside your PC. ATI's recommendation is that the X1300 is suitable for 480p and 576p playback and the Radeon X1600 720p playback, with only high-end Radeon X1800 boards having sufficient processing power to cope with full-on 1080i and 1080p High Definition content. This may come as something of a disappointment to anyone who has bought a lower-end X1000-based board in the hope of playing 1920x1080 H.264 content, but sadly it's a simply case of logistics - The higher the video quality, the more pixel pushing power is required to accelerate it.
Check it out over at EliteBastards.