My will to play pretty much ended mid way Wrath (was playing since december 2004). The developer team change really hurt the game. Tom Chilton, aka Kalgan, wasn't the best pick for the job in my opinion. Still I did raid Icecrown, had to fight the Lich King.
Cataclysm nuked my will to play for good. Retcons galore, lorelols left and right (I play warcraft since the very first game in the 90s, story matters a lot to me), dumbed down talents, some of the area revamps too, specially forsaken cities (Brill hit me the hardest, I loved the area before, the tavern had that unique music from one of the razorfen areas).