Things you can do if you want to help:

 - UI for inviting a contact in a chatroom.
 - UI for accept/refuse invitation to join a chatroom and VoIP calls.
 - GtkWidget-ify libempathy-gtk. Actually most window/dialog do not inherit from
   GtkWindow/GtkDialog. Need to create a glade catalog, it seems to not be
   that easy.
 - Remove Quit option everywhere, empathy is a session service and shouldn't be
   leaved.
 - Add sound events
 - Add register capability in EmpathyAccountsDialog if the profile says
   it's supported.
 - Write a manual based on gossip's.
 - Reviewing File Transfer patch, see bug #462172.
 - Drop libtelepathy and use telepathy-glib instead when it gets client-side
   functions.
 - Drop Nokia's MissionControl and use the standardized MC spec instead.
 - Improve VoIP support once stream-engine gets cleaned and moved into tp-glib.
 - Split MUC out of Empathy's main program and create a xchat-gnome-like
   program for MUCs.
 - See with Gnome Online Desktop project how to implement meta-contacts and
   merge information from multiple contacts.
 - Testing and Bugfixing.

If you want to contribute you can ask for information at
 - #telepathy on freenode
 - Telepathy's mailing list: telepathy@lists.freedesktop.org