The OpenELEC Linux distribution that aspires to be a leading multimedia OS within an entertainment center is nearing its 3.0 release. The OpenELEC 3.0 Beta was released and now it's based upon XBMC 12.0 Frodo...
You missed the XVBA support. oe 2.0 was the first mediacenter on linux ever, that was released with stable xvba support to decode H264 and VC1 on AMD UVD hardware.
oe 3.0 also has that kind of support integrated + some bugfixes that came alive after the testing of oe2.0.
oe3.0 ships xorg 1.12 in order to be able to support fglrx-legacy.