I started this game with nothing all the way back in Vanilla. Didn't even know what a raid was. Worked up t pugging ZG, to getting in a raiding guild running MC and BWL and was just about to start on Naxx.
Loved the game.
Levellup up in TBC still with virtually nothing but a bit more experience, eventually working my way towards server firsts in Leo the Blind, Tidewalker, up to server firsts Muru and Kiljaedin.
Loved the game.
Went on in WotLK to get Deaths Demise and Celestial Defender and some other server first bosses that i cant even be bothered to remember.
Found the game boring.
Dont know whether its because end game WotLK sucks, or simply because i am bored of it all.
Quit my main, went back to levelling alts. Find the game much more fun just levelling atm and getting my proffs maxxed out.
When Cataclysm arrived i will have a choice of 3-4 levell 80's to choose from as to what i want my new main to be.
I spent months and months getting EVERYTHING on my old main, got 9.2k achieve points, stopped when HC Anub went down, cba to try ICC heroics and raids on my main, will get to them on one of my alts.
tl;dr - Yes alot of server firsts / world rank kills, dont feel special, dont care to feel specials and totally and completely bored of the WotLK end game, its much more fun to level. Dont miss WotLK raiding one little bit at all.
oh and edit - lucky enough to get server first black dragon from sarth 3d 10 man too, all the way back on january 10th 2009