It's true, after you've run UBRS about 50 times or so, you've pretty much got it down to a science. You know what to do with the pulls, you know all the sayings Rend and Nef shout out, you know to tell Awbee to quit his stupid whimpering, and you know that the dragons in Drakk's room can't be slept. It's not that it's not fun-- it is. But like Burke says, it's fun in the rehearsed ballet sense rather than the-- well, the "OMGBBQWTF just happened!!?!!" sense.
So like Burke, I too am hoping Blizzard delivers on the WTF in the expansion. I can't wait to run instances I don't know yet, or figure out how to do pulls I've never done before. I can't wait to see something drop that I've never read enviously about on Thottbot, or find an easter egg that I haven't yet heard about. Burke uses the Son of Arugal as an example of a WTF moment, but I'd say even something like the end of Maraudon, with the beautiful landscape, the epic bosses, and that gnarly Princess-- that's the stuff I can't wait to see when Burning Crusade finally comes around..