There's no vlc player just yet. I was going to port it to Maemo, but have been too busy lately on getting another app done to do so. If no one else takes up the project by the time quick.launch is completed, I'll gladly work on getting vlc work started.
I believe VLC supports many more codecs than Mplayer. It also has excellent support for on the fly transcoding/streaming of DVDs and other video sources.