Datamined from the PTR, new Worgen and Goblin Masks, and speculation starts if the are the new races in patch 4.0.
Goblins are, like World of Matticus said, Ferengi. They work for both sides to make the most money. It would be interesting to see which classes they would get. Warriors, for sure I guess, mages, rogues, priests, warlocks and hunters are also conceivable. But do you see a Goblin Paladin or Shaman, or a Goblin Druid, probably not.
Worgen from Gilneas (look that up on wowwiki), not alligned with the Alliance, or the Horde for that matter. Classes would be warrior again I guess, and they are close to nature so maybe shamans? No paladins for sure, and hunters... meh, wolfs taming wolfs, seems unlikely. Mages and rogues could be an option, but warlocks... maybe.. oh... and Druids of course.
They are called Worgen, not werewolves, and even then, a lot of literature already is mentioning just weres, humans able to shapeshift in different forms... so, a worgen Druid would not be that farfetched, and again the nature theme ofcourse.
Also the fact that both races are not-alligned gives the speculation that they start as neutral, and that later on, at level 20 I guess, you could choose your faction, either Horde or Alliance... now that will be interesting.
But speculation is still speculation.... but alas, that's also a part of World of Warcraft
Goblin Warriors, Rogues, Mages, Hunters, Priests
Worgen Warriors, Druids, Shamans, Warlocks, Mages/Rogues
...oh, and Death Knights of course... /sigh