I just stumbled across this, which is very very handy.
You may have noticed now that quite a lot of YouTube clips have got an option to "Watch in higher quality" - They've actually increased the resolution of the video, the sound quality, and changed the encoding type. Because the higher quality clips are in MP4, you can download them and play them if you have got Quicktime installed (Or if you think Quicktime is the devil like myself, something like
this can play MP4, and every other format!) rather than having to download a dedicated flash movie player.
Anyhow, check this:
http://googlesystem.blogspot.com/200...mp4-files.html 