Have you reviewed
this page? Once you have the DivX codec installed and configured then recording videos from in-game should be no problem, which can then be
posted on YouTube.
Alternatively you can just zip up your replay files and attach them to a forum post to let other players download and view them in Clones. The files are stored here:
C:\Documents and Settings\[user name]\My Documents\Clones\Profiles\<player name>\Playbacks (WindowsXP)
or
C:\Users\[user name]\Documents\Clones\Profiles\<player name>\Playbacks (Vista,Win7)