With the latest ati 10.5 beta drivers one of the latest strongholds of nvidia has begin to fall. Ati can decode now h.264/VC-1 firstname.lastname@example.org level with 16 reference frames.
Page is in Czech but the interesting part is the video (min 6 is the best part).
So, now that ATI is getting ride of nvidia on windows side, let's hope they reserved some energy to conquer things on linux territory. :D