Action Comics #841 and #843 both make references to there being a 3rd Kryptonian on Earth. Superman indicated that he and Supergirl are the only two he knows, so who's the 3rd and why isn't Power Girl one? Isn't she from Earth-2 Krypton? And what about Match? (not sure if he's a clone of Superman or a clone of Superboy) It could be that the Kryptonian kid in the next arc "Last Son" is already on Earth, but one would think that the ship heading towards Earth is carrying him/her.