Well I'm under the impression that the existing lore will be changed, especially going off the new class descriptions they put up. Thaumaturge's stands out the most:

Thaumaturges are casters who command spells of the six elements to wreak havoc on their enemies. Their unparalleled devotion to the realm of magic endows them with the largest MP and smallest HP pools among all the classes. Though known for their inherently weak defenses, thaumaturges are feared for the destructive forces they wield. Specializing as a black mage serves to further strengthen class characteristics and also increases MP. Black mages are able to invoke devastating spells of ancient magic and subdue multiple enemies with a single cast.
Sounds like a lore change/re-write to me, IMO.