Oh look, a filthy Alliance player! Female trolls are the master race.
Cataclysm was pretty bad on the whole but I was addicted enough to stick with it. MoP was actually pretty good as far as raiding and when I started playing again at the start of Warlords of Draenor I really enjoyed the questing and the raids but I just couldn't devote the time to it any longer.
Wrath of the Lich King will always be my favourite, though. Probably nostalgia more than anything else, but I loved Ulduar and Ice Crown Citadel.