Reader UnstØppable writes in with a question I thought would benefit others: "Does the Bladestorm aggro problem ever get better? What I mean is, I've seen it countless times, the arms warrior enters the dungeon, the tank lets out a sigh (sometimes it's me), we pull the first group and everything goes fine, until he hits that Bladestorm button. That's when somehow he manages to pull aggro from every mob and their mom and makes both the healer's and the tank's lives hell or usually ends up dying within seconds."
Part of the problem here is that certain classes/specs have no aggro dump or reduction ability and as a result their big DPS moves generate a lot of threat. Arms warriors, most DPS death knights (at least the blood and unholy specs I've used) and retribution paladins have limited aggro reduction at best (pallies at least have Hand of Salvation but that's a band aid at best) and while tanking threat (especially AoE tanking threat) requires ramp up time, it's very easy to hit the Divine Storm, Death and Decay, Pestilence, Whirlwind or Bladestorm buttons. (Enhancement shamans with Spirit Weapons seem to be okay, I rarely pull aggro even when I go nuts with Fire Nova.)