First off, this is hardly official. It's more a matter of putting 2 and 2 together. :P
A few days ago, I posed this question in the "Ask the Devs" thread in the Killzone 2 section of the PlayStation.com forums:
To which E0N, the GG developer charged with answering questions, responded:
(see the 2nd post on this page to see his response)
Then, just days later, somebody posted a 1UP article from back in August, in which Steven Ter Heide mentioned a 2008 release date for Killzone 2. E0N later references this, saying:
I believe somebody found footage of my esteemed Head Producer and Creative Director confirming that we were aiming for a 2008 release date. I'm certainly not in a position to contradict that - as I'm sworn to secrecy.
(first post on this page)
So, due to my vague and crafty questioning, combined with the research of other PlayStation.com members, I've come to the conclusion that they are aiming for some point in 2008 to release the game, have been aiming for this point for quite a while, and are still on target to hit this unknown date.
Also, I think that the date falls around September sometime, as SCEA's Scott Steinberg lists Killzone 2 as releasing after Socom: Confrontation in the Summer, but before Resistance 2 in November:
Let's break it down by calendar. It makes it a little easier to keep them organised.
[...]
SOCOM: Confrontation shipping in the summer. SOCOM is also one of those emblematic PlayStation brands. Multiplayer. A lot of folks have grown around the PS2 [version]. Killzone 2…not quite new IP, but certainly not an established brand like SOCOM. That will be a huge FPS title.
