If you've been thinking about rolling one of the new class/race combinations, but haven't really been impressed by the ones they announced a ways back, you may be in luck. Lead systems designer Ghostcrawler has confirmed that troll and dwarf warlocks will be coming with Cataclysm.
There's no word yet on the lore behind this change, but between Zalazane on the troll side and the Dark Irons on the dwarf side, it seems likely there's good enough reason to unlock the class. Now if only we could get them to give us Worgen paladins, we'd really be cooking. Stay tuned to WoW.com, there's more juicy Cataclysm info to come.