Each passing week i doubt more and more we will get a WoW expansion at blizzcon.
I can only see them announcing 8.3 at blizzcon if there will be such a patch at this point.
Especially because well we dont know anything about the future.
Aside from that there will be a 9.0 coz else they would have fixed all the classes and stuff.
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cata did it fine, it wasnt a main focus in cata. Raiding and endgame stuff was related to deathwing etc and world threats. instead of war between the factions.
There were skirmishes and battles. but it wasnt main focus.