During the Warcraft the Adventure Continues panel someone asked a question related to paladin lore mentioning a book from a quest back in warcraft 1 I believe. Anyway it lead to the devs answering that there will be a lot of paladin lore and of what the light is ect. Next class quest a la warlock green fire? God I hope so.
Sounded a lot as though we might be finding out more about the Naaru. Not sure the answer was hinting at something as concrete as a class quest though.