Well, if you put two and two together and cross your fingers, it doesn't seem out of the realm of possibility.
A reader has informed us that the latest issue of Edge magazine has confirmed that Guerrilla Games is currently working on a "Killzone follow-up."
It seems the majority of the development staff is already cranking away on the next installment in the fantastic series, with KZ2 and KZ3 Senior Producer Steven Ter Heide acting as game director for whatever this "follow-up" is (presumably Killzone 4 ). Guerrilla also announced a while back that they're working on a new IP; obviously, this isn't it as the Killzone franchise is definitely involved.
There's something else to consider, too. Sources have been saying that internal Sony studios are already working on PlayStation 4 game concepts and in fact, there was the rumor that at least one studio has stopped working on the PS3 altogether so as to focus on the PS4. Therefore, if it's Guerrilla, doesn't that mean that the next KZ entry will be on Sony's new console? Dare we hope?