My favorite thing about expansions (and to a smaller extent patches) is going in blind. Having no idea what the bosses are like and seeing a piece of gear and thinking, "Woah, what is that? How do I get that?!" After a few months all the regular players will basically know everything, but for awhile there we're stepping into the unknown and I love it. So whenever I do a new dungeon in an expansion I ask my party to please not tell me any boss mechanics or strategies. I love to go in blind at least once and fight bosses with quick wits instead of muscle memory.

So yeah, bring on the wipes.