I have not played for a long time... since a few months before the level cap increase actually. I remember back before then increase when everyone was meriting on colibris no one wanted a BLM for obvious reasons.
Now I hear that BLM are highly recommended while leveling in Abyssea. That being said, I'm curious as to what else has really changed for the current "endgame" when it comes to specific class roles.
edit - I know that blm going from not desired to desired in the standard party isn't exactly a role change, but I'm curious about any others.