A few stealthy souls I know have been working on this: http://www.mmomeltingpot.com/2011/11/rogue-legendary-dagger-in-wow-patch-4-3-the-weapon-the-stats-the-proc-the-quest-line-the-wings-and-yes-how-long-it-takes-to-get-them/
It's a good thing they have the pocket-picking ability, because even just to start it I was told takes about 10K.
Poor Rökkr--she and my Death Knight Morphemia were the second and third characters I started, and by far the most neglected. Not sure even legendary weapons will inspire me to play my rogue more, and am seriously considering sending Morphemia to boarding school.
But, damn....batwings? /sigh.