Joost uses an H.264 codec (aka AVC, aka MPEG-4 Part 10, aka ISO/IEC 14496-10) called CoreAVC, created by CoreCodec.
When will there be a Linux version of Joost?
If you have version 9.0.115 of Flash or later installed and use Firefox 3 then the Joost Player should work well within the browser, you may find issues in full screen.
