Unfortunately, it missed some features I need : easy shortcuts and above all, a "pause" feature. You know, the one that is needed when your boss want to talk to you just during that crazy guitar solo.

So here is what I added in my Emacs config file:

(global-set-key "\C-xwf" 'emms-next)
(global-set-key "\C-xwb" 'emms-previous)
(global-set-key "\C-xwq" 'emms-stop)
(global-set-key "\C-xws" 'emms-start)
(global-set-key "\C-xwp" 'my-pause)
(defun my-pause ()
  (start-process "pause-ogg123" nil "pause-ogg123"))

pause-ogg123 being a simple shell script that I've hacked because I was too lazy to do that in elisp:

if ps auxw | grep ogg123 | awk '{print $8}'| grep -q ^T ; then
    killall -CONT ogg123
    killall -STOP ogg123

If someone has a more elegant solution than sending signals to ogg123, I'd gladly accept any patch. :-)