That's updated my qualifications.
The quest that tipped me over, Unwelcome Guests, was one I'd meant to hand in a bit earlier, but I was juggling three other long quest chains in the Storm Peaks and hadn't got round to it. I happened to pass nearby Frosthold, so popped down and claimed it.
This time round, the levelling wasn't quite as grin-and-bear-it as I was expecting. There were some interesting new mechanics buried in among the increasingly-fanciful ways of saying "kill 10 rats"; I particularly liked the potential that the vehicle ones had (they're a bit dominant strategy at the moment, but I'd expect that will change in future patches). I didn't like doing them, but I liked the options they opened up. Time seemed to pass quicker this time round than it did with the Burning Crusade expansion (perhaps because I had a break in the middle when I went to Atlanta).
As before, I've not actually seen everywhere because I wasn't racing to level up, so I exhausted all the soloable content in a zone before I moved up. I'll therefore probably take another character up to 80, too, just to see what else there is. I'm not sure which one: the paladin is easier to get into pick-up groups for instances because she can heal, plus I've maxed out her skills and it would seem a shame to waste them; however, if I take the mage up then she may be able to solo upper Blackrock Spire and finally get that last piece of her dungeon tier set that she would have had at level 60 if TBC had come out a week later.
Oh, decisions, decisions, none of them meaningful...