Hopefully this means that other AMD chips are supported too such as the HD 4670 and the 6750M
The Video Decode Acceleration framework is a C programming interface providing low-level access to the H.264 decoding capabilities of compatible GPUs such as the NVIDIA GeForce 9400M, GeForce 320M, GeForce GT 330M, ATI HD Radeon GFX, Intel HD Graphics and others.
Hehe, I was about to suggest looking at that other process... I fell for it tooScrap that, I'm sorry. There's no hardware decoding. The CPU usage is low by player but there's a decoder service active while playing the movie which takes around 40% CPU.
Apparently it's already enabled for ATI in 10.6.x:
http://developer.apple.com/library/mac/#technotes/tn2267/_index.html
While SL had the hardware decoding feature only on 9400M and 320M chipsets, Lion does have this for dedicated GPU cards it seems. With my HD5870, while playing a 1080p Quicktime movie, CPU usage is 7%.