Example prime might be the Ethereals. They were an amazing group. The Consortium was Goblins except with actual charisma, business savvy, common sense, and inventions that worked. The Protectorate was a pretty badass group of elite fighters battling the forces of darkness. Even the Ethereum had a story of tragedy and corruption to make the Scarlet Crusade look like amateurs at the whole fanatic game.
But in Wrath? Okay, we get some Ethereum hanging out with Malygos' posse, but that's it. Poof. Ethereals are all but gone. I would have loved to see them selling their Eco-dome tech to settlers in Northrend's snowy areas or something, or handing us monthly gem bags for Frost Wyrm Ivory.
Same thing with the Arakkoa. Rilak the Redeemed seemed to herald a race ready to break free from the influence of dark gods like Terrok and perhaps play a part in the Army of the Light itself. But they're missing. Even Wrath has its examples. Tuskarr disappear after Dragonblight. The Kvaldir are perhaps the most menacing enemies in all of Wrath, a clan of hulking sea spirits who appear out of a malevolent, all-encompassing mist to plunder and burn, leaving devastation in their wake. Seriously, they're amazing. Garrosh's Landing may be the most menacing looking area in all of Northrend, and doing the quests there felt amazing due to the atmosphere of the fog and the longboats and the seaweed encrusted Kvaldir glaring angrily.
Now admittedly, we are apparently getting more Kvaldir in the new daily quest areas of Patch 3.2, but Vykrul are always awesome enough to deserve more.
So anyway, that brings me to a question: What races and organizations do you feel have suddenly dropped off the face of the earth and gotten the short end of the stick? Which of them would you like to see return in the Maelstrom?
Me, I'm hoping for the Kvaldir revealed to be servants or thralls of Neptulon, and the Ethereals to start a Trade War with the Goblins, perhaps with the Alliance as their favored customers to balance the whole Goblin-Horde dynamic. But anyhow, your turn. There's certainly plenty of old allegiances and old rivalries that it'd be great to see return in a future patch or expansion.