But not many games available yet. Most of my steam games are from humble indie bundles, hence have linux versions. Only a few of those games have made their linux versions available through steam.
BTW-- steam runs well on my Kubuntu 12.10 x8-86_64. I have a GTX 650 TI
Vorbis is an excellent audio codec. VP8 isn't as good as h.264, but it does the job for low res vids I use xVid for alot of my higher RES vids. H.264 also has tons of hardware support, VP8 could possibly match h.264 with that kinda support.