Audiophile Linux : http://www.ap-linux.com/

Looks interesting but I noticed the Kernel is quite old.

I have also see some talk about Voyage Linux


Music Player Daemon comes up as well as OSS and Jack


Music Player Daemon :
http://mpd.wikia.com/wiki/Music_Player_Daemon_Wiki

More Linux Bit Perfect Talk:
http://www.head-fi.org/t/561961/bit-perfect-audio-from-linux

Multimedia Software

JRiver Media Center seem to be a popular windows choice. I want to use Linux so I will have to find an alternative.

Doing a search at alternativeTo listed some known an unknown possibilities.

http://alternativeto.net/software/j-river-media-center/


The ones I am familar with:

XBMC

OpenELEC

GeeXboX - Currently using this one

MythTV and all its derivatives

LinuxMCE


The new ones I am not familiar with are:


Plex

Freevo - Forgot about this one

Miro

MediaPortal

Hulu Desktop

Enna - Looks dead

Serviio - Based on Java and has a paid "Pro" version

Twonky - Cool name

TVersity

TVMOBiLi

The real question is what software package plays audio the best?

Even more options:

Vortexbox

mpdPup based on Puppy Linux which I like:
http://murga-linux.com/puppy/viewtopic.php?p=662898