This addon plays Jammal'an the Prophet's "Join Us!" upon successfully casting the Dominate Mind spell (priest's new* mind control talent).
This spell is for people with an ever so slight proclivity towards Defenestration.
(And maybe for CC.... but really, who uses it for CC, when you can utilize it for hurling your adversary into Lava....)
*Used to be a learned spell called Mind Control, is now a Talented spell, called Dominate Mind.