A lot of people say oh its a different game. From what Ive gathered they have a ilvl bump and to offset that the bosses deal 10-15%(?) more damage. They get separate locks outs raidwise10 and 25. (Dont recall if that applies to current or previous teirs.) cant show skeletons or bones so spells have diff icons and and death=tombstones. Thats all I can think of atm. Boss mechanics are the same you still need tanks healers and dps to down stuff so unless im missing something at its base game play as far as raiding goes is the same. That is unless someone can elaborate on what makes things so blatantly "different"