Is there any reason to go beyond the Honored Status with the Black Prince? I already have the quest to get the 10 sigils of power and 10 sigils of wisdom. Unless having them exalted will be needed to progress the legendary quest line in the coming patches.
UPDATE 11/2/2012 (Patch 5.0):
Just got honored with the Black Prince and I can no longer get rep with him. So they must have it where you cannot get above that from killing Mogu or Ik'thik. Unless it can come from raids, but I have yet to do a non-LFR raid to try this.