For some time now there has been a UPnP plugin based on Coherence(Now grilo) for Rhythmbox. It allows Rhythmbox to access UPnP/DLNA MediaServers on the network and will also export the Rhythmbox music collection to other UPnP/DLNA MediaRenderers such as the Sony Playstation 3.
Fist add grilo ppa:
sudo add-apt-repository ppa:grilo-team/ppa
sudo apt-get update
Then You can install it using
sudo apt-get install grilo grilo-plugins
Then go to pluings->grilo media browser. And configure it.
See more details here:
http://bernaerts.dyndns.org/linux/74-ubuntu/240-ubuntu-precise-upnp-dlna-client
http://coherence.beebits.net/wiki/RhythmBox