Our sources have told us that the new races of Cataclysm will be:Personally, I don't believe it. Goblin's are a neutral race within the Warcraft lore. It would cause a ton of lore-based conflicts within the game world. Not to mention how out of place some places of the game world would feel. Goblins joining the Horde would break too many parts of World of Warcraft.
* Worgen – Alliance
* Goblin – Horde
This doesn't mean Blizzard can't make it work. Blizzard could update the entire world and switch all the Goblin content over to Horde content. This would be out of character though, as Blizzard has shown that they'd much rather create new content rather than update or fix old content.
In the rare case that this does prove out to be true, Blizzard will probably just spin off some sort of new Golbin tribe (or whatever Goblin groups are called) and attach it to the Horde. Thus, they have nothing to do with the current Golbins in game. Blizzard is more than free to invent whatever they want. I just don't think it will feel right for WoW.
Worgen? Who the fuck cares about the Alliance.