When you say "media" player, does it concern stricty video playing or should the default media player be suitable for both video and audio? Personally I like to keep these two separated, I feel that a specialised player will best fulfil its purpose than a multimedia player like Windows Media Player.
I love to use VLC to play videos, because it's simple, work out of the box and efficiently. I have some issues with it (it doesn't manage to play some videos with recent hi-res codecs), but I think that is related to my crappy hardware - actually my whole Mandriva install is crumbling apart. When I have an issue with VLC, I use mplayer directly. VLC is one of the most popular video players in France (maybe because the VideoLAN project began in Paris?), but I don't know if it is widely used in the rest of the world. I agree that the play-list of VLC is a bit strange, but since I don't use it to listen to music that's not a big problem for me. For playing music, I use Clementine, for I liked Amarok 1.4 but I can't stand Amarok 2. Before I discovered Clementine, I used Quod Libet but I think that it is more suited to a GNOME environment. Cheers, Rémi / Akien.