Forever Assist commentary
Paladins took the biggest shake-up. Positions, rank counts and prerequisites changed in all three trees at once, so any talent plan made during name reservation needs a fresh look. Protection gets Redoubt at 30% for far more frequent blocks, while each Holy Shield hit deals less. The weight shifts toward surviving on block count and building threat, which arguably makes Prot steadier as a 5-player tank.
Feral Druids trade Berserk for a Primal Bite and Lacerate core, adding threat tools for bear tanking, and Restoration gets a clearer roll-then-burst HoT flow with Bloom and the new Swiftmend. Mages get Ice Lance at 300% but with an 8-second cooldown, ending freeze-and-spam Ice Lance play. Arcane Blast is easier on mana while leveling but hits a little softer. Shadow Priests should save Shadow Word: Death for finishing blows.
None of this was explained by Blizzard in a post; it was found in game data, so intent and exact numbers should be re-checked once official notes appear. Paladins and Druids in particular should rework their builds on the new trees before re-spec costs kick in after the Nov 4 launch.