It looks like Lady Katrana Prestor, also known as Onyxia, is alive and well, and is being set up to be deposed by the returning king. As a pre-BC Alliance raider, I can't really get too excited about that, because I remember how in depth and epic the Onyxia key quest chain was, and I remember the rush when I first killed Onyxia and we headed to Stormwind to turn in her head.
Sure, it's true that it's difficult for an MMORPG to make a non-static story change, and you can't expect the credit for Onyxia's kill to go to any certain guild or group in game. Still, at least for the Alliance side, the story of how she was unmasked and defeated is pretty epic in and of itself.
It starts with Marshall Reginald Windsor, a legendary knight of the Alliance, once wielder of the epic Ironfoe. He goes on a desperate quest into the territory of the Dark Iron Dwarves to find the evidence he needs to unmask Lady Prestor's duplicity and restore order to the kingdom. He finds the evidence he needs -- a prophecy from the halls of Karazhan itself -- but is taken captive by the Dwarves. After you break him out of Blackrock Depths and recover the tablets that hold the prophecy from the Dwarves, you head to Stormwind itself, where you march gloriously through the streets of Stormwind while the guards salute you, barge into the throne room, unmask Onyxia, and free Bolvar Fordragon from Onyxia's mind control.
And honestly, that description up there? It doesn't even begin to describe the actual epic feeling of the quest line. Actually going to Onyxia's Lair and slaying her almost feels anticlimactic compared to the events of The Great Masquerade, although watching her head being lifted to adorn the gate of Stormwind as a warning to Interlopers is awesome in and of itself.
Even if it is the King himself who will defeat Onyxia, I'm a little sad that that victory is being taken away from us, and possibly from Marshall Reginald Windsor, a vertiable man among men. If Varian defeats Onyxia singlehandedly, will Marshall Windsor and the compelling story of his brave struggle to find a lost prophecy be written out of lore altogether? Will Bolvar never get to prove his honor by breaking free of Onyxia's mind control and slaying her honor guard? I honestly believe that, should the WoW comic take that tack, Warcraft's lore will be poorer for it.
At the least, maybe they can split the difference and have Varian meet Windsor and Bolvar at the gates of Stormwind and confront Onyxia and the false King Wrynn together.