I tried MPlayer but it just refused to work. Maybe I'll give it another go, it was a while ago. VLC's not been too bad so far, doens't have all the features of QT but for stuff like avis it saves having to convert files and the like.
MPlayer is free and it works better than that M$ garbage. MediaPlayer can't even keep a constant frame rate, MPlayer plays smoothly for me, and there are better viewing preferences.
MPlayer is free too. VLC is free too. Both are opensource projects (well, VLC is to a certain extent), and both read moreorless ASF and WM data. 'Moreorless' because this format is so sh!tty that you will still bump on a few weirdly encoded files.
Just out of curiosity, airbrush why do you keep pointing out that MediaPlayer is free? We are well aware of that, by it being free doesn't make it any better, nor should I give praise to M$ for making the app.
I thought it already did ... I remember clicking on a .wmv stream/movie in Safari and VLC launched and played it. Have you tried the latest version (0.7 AFAIK)?