Any-way, yes quicktime pro can play H.264 files, as well as encode them, but i fear the functionality is almost purely software encode/decode, and thereby cannot make use of the r600 hardware.

the software needs to know that the r600 is there...and while quicktime offers hardware DX9 acceleration, this is purely shader acceleration, and is yet again more software that is not aware r600 even exists.

I know the prices of the player are a bit steep, Sampsa, but it might be worthwhile to get a BD or HD internal player for reviews...but you also have to have an HDCP-compliant monitor for playback!