All that's been said is Kira Yoshikage DLC. It's safe to assume it's a DLC outfit (probably the guy he takes the form of later in part 4) or possibly something do with Jojolion Kira Yoshikage.
Either way, a confirmation of Kira is friggin awesome. Also, keep your eyes open for February 16th. Apparently there's going to be big announcements involving this game.