voted Exaile. intuitive and full of features. i know it copied Amarok, but this is what i use (for GTK+).
btw, its progress bar is priceless when looking for specific speech parts, in contrast with "standard" GTK players like Rhythmbox or Listen.

Songbird of course. I love Mozilla because of Firefox, now they have build a music player which is almost finished with many easy to install add-ons. Yah.

Voted Amarok:D

used amarok , banshee. nice ones

VLC
 

VLC is definitely my favorite. Why isn't it on the list?

I'm not really for playing back media on linux.
Too often I noted not enough driver support.
In the past I could not playback video except dirthered, and by the time the videodrivers where available, I couldn't find .mkv or .ogg decoders.
my all time favorite is mpc, windows only.
Edit:
Other than MPC,I tried zoom player and VLC. the latter being better.

There can be no other players but XMMS - one and only :)

mp3blaster?

What, Herrie didn't make the list? Everybody I know uses Herrie! Well, actually I've never met anyone who uses it besides myself... But I'm sure there must be at least 20 or 30 million out there... somewhere

xmms...but I use mplayer for everything...sights and sounds

mpg123 is better

a good question, where is moc? ;(

Amarok is the media player for Linux today, even though, I use mostly Rhythmbox. However, if you ask me, the player with most potential is SongBird. The ease way of installing addons and skins, pretty much like Firefox, may give it an edge in the future. That, and the fact it works easily and consistent across platforms may yet play an important role in a few years.

amarok

Moc, which isn't in the list.