These players have more in common then not. Audacious seems to have more options though and supports WinAmp skins. If you are looking for a linux app to replace (the look and feel of) WinAmp these are the two best options I’ve found, slight edge given to Audacious. Although, I personally like the qmmp default skin better. Other than options, they are practically the same program.
So Audacious “wins” cause they have more plug-ins, options, and skins by default. Also they have a voice removal pluging (a little bit buggy) but quite awesome if you want to get some karaoke going. I will definitely be looking for that feature in more music players. (Neither is continuing in my review, as they are competiting more with each other, than the others)
Who’s left? Amarok, Ario, aTunes, Banshee, Sonata, gmusicbrowser, Videolan Client, Quod LIbet, Exaile, Rhythmbox, Sondbird