Tekken Tag Tournament 2 is due out in September, but more characters will be incoming sometime later. Today we got confirmation on the four fighters due in the first downloadable content pack, with a short video that highlights each one.
The trailer announces that Michelle, Ogre, Angel, and Kunimitsu will make up the first set of DLC characters. This announcement may seem extremely early for a game not due until the fall, but keep in mind that the pack will be delivered free-of-charge--unlike some other high-profile fighting games.
Tekken producer Katsuhiro Harada has taken a stand against charging for DLC characters. He commented recently that he sees them as essential as chess pieces, and he would "never sell" them individually. He did mention, though, that he's open to selling cosmetic DLC like alternate costumes for a charge, since those items could be created in response to fan wishes.