In addition to the existing .MP4 support, Twitch users can now upload H.264-encoded videos in MOV, AVI and FLV formats. That's still half as many as YouTube supports, but it's a big step forward that should accommodate the needs of most users. Twitch's upload tools have also been updated to include a default language setting and longer tags -- up to 100 characters per individual tags and 500 for all tags total. Finally, Twitch has fixed a ton of small glitches, including a issues that kept users from uploading custom thumbnails and an experience-ruining bug that caused videos to restart near the end of their runtime.
While this update is relatively small, it shows how serious Twitch is about competing with YouTube's vast library of non-live gaming videos. Twitch also says the improvements are the result of community feedback, and says more user requested features (like bold and italic text formatting in video descriptions) are on the way.