Update: As Jeremy points out, the update has been synched. All should be well now.
Update: This post only applies to the package on 12.10 and will be fixed when Ubuntu resyncs Rygel from Debian.
It seems that the Rygel package is missing some important files which renders the transcoding non-functional.
A work-around is to download the files from http://git.gnome.org/browse/rygel/tree/data/presets
and drop them into