Bungie has confirmed that they will be working on a “massively multiplayer action game.” Initial rumors said that the game was WoW in space although Bungie lead network engineer David Aldridge claims this approximation is not the case.
Bungie has hinted at in the past an interest in a persistent world game, although they have never developed such a game before. The game, games or whatever it ends up being will be published by Activision.
Bungie added something about it being a joke but its hard to say whether they’re just trying to cover up for a broader announcement they’re not ready to make.
Source: IGN