The King is Dead! Long live the King!
Dalaran had a wonderful feeling of 'coming home', with music to make your heart melt and streets full of players in transition.
Wintergrasp, although it degenerated at the heart of the action into a slideshow, was just pure, unadulterated fun - and it really didn't matter if you were a pvp'er or not.
Icecrown and the Storm Peaks were just majestic, and for me, pretty much every map in this expansion had a score which shone with feeling and in hindsight, melancholy. because i miss it.
Cataclysm makes me think of 2 words repeatedly :
" I Miss..."
Not because it is a bad expansion, but because everything has turned into 'insta-queue', and with the Deathwing raid being released - degenerated into a ridiculous LFR 'free epics for everyone' scenario that completely removed a sense of achievement from a game which use to offer so many challenges.
I guess the nostalgia and waning interest is a natural progression in a game which endeared itself to us for so long, but Blizzard's decision to give players everything they want for minimal effort has unnecessarily accelerated my time away from Azeroth and beyond.
I still return sometimes since i am a pvp junkie and still enjoy a good scrap (especially after a few beers!), and will keep tabs on Mists of Pandoria, though i can't see it being much more than a short term injection of adrenaline.