Saurfang, Grand Awesome-Guy of Orgrimmar and former leader of the Might of Kalimdor, has traveled to Northrend to keep an eye on Garrosh Hellscream.
Garrosh Hellscream has moved away from Nagrand in Outland to join the New Horde. He's currently in charge of Warsong Hold, and Saurfang fears he may be following the same dark path Grom Hellscream did.
Naxxramas has returned along with its master, Kel'thuzad. Kel'thuzad isn't just sitting idly, though. You can see him here commanded an undead legion against the outskirts of Warsong Hold. You can't see most of his minions in this shot, because they're off chasing player-controlled Siege Tanks.
The Royal Apothecary Society has taken their experiments to the field. They seek to wipe out the Scourge and all who still live, according to some of their apothecaries.
Commander Eligor Dawnbringer is back, lending a hand in Wintergarde Keep.
Archmage Arugal has been recruited by the Lich King and now calls Northrend his home. Arugal's worgen and wolfcult followers support the ranks of the Scourge.
Gryan Stoutmantle has received a promotion to Captain, and the Westfall Militia has become the Westfall Brigade. They've relocated to the Grizzly Hills, lending a hand in the war against the Scourge.
The Amani Trolls didn't quite finish the job when they stuck a spear in Harrison Jones. He has since moved on to studying the Drakkari.
The Light's Hope Chapel crew lends the Argent Crusade a hand up in Zul'Drak. The Orc fellow there is Eitrigg, friend of Tirion Fordring and former advisor to Thrall. He's signed on with the Argent Crusade, too.
Prigmon of Mojo fame and the rest of Budd Nedreck's band has, unfortunately, returned. Luckily, Budd Nedreck isn't in charge anymore, cursed by his plots in Zul'Aman. I somehow feel better about helping these guys out when I'm not answering to Budd.
Hemet Nesingwary is back, of course. This time he has set up camp in the Sholazar Basin, a tropical anomaly in the west coast of the frozen north. Don't worry, his quests aren't nearly as mind-numbing this time around. I would go as far as to say they're fun!
The Explorer's League is still here, of course. They've focused their full attention on Northrend, and have started many digsites to uncover the mysteries of the Titans. As usual, they've managed to unearth horrible, horrible evils. What a shock.
All Old Blanchy really wants is some oats.
The Scarlet Crusade has taken to Northrend's shores under a new name: The Scarlet Onslaught.