Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
In the latest issue of Linux Journal, the readers choices were presented, and the winner among the multimedia player were VLC. Personally, I like VLC, and it is my player of choice when I first try to play a video file or stream. Only if VLC fail will I drag out gmplayer to see if it can do better. The reason is mostly the failure model and trust. When VLC fail, it normally pop up a error message reporting the problem. When mplayer fail, it normally segfault or just hangs. The latter failure mode drain my trust in the program.
But even if VLC is my player of choice, we have choosen to use mplayer in Debian Edu/Skolelinux. The reason is simple.