Sony US has explained that it moved Killzone 2 to February 2009 so the game didn't end up competing with others in its own catalogue.
The decision was purely a management one, explained Sony US speaker Ron Eagle, and nothing to do with any development problems.
"Killzone 2 was moved to Feb 2009 to make sure we didn't have three shooters in the marketplace competing for retail dollars during the same holiday season," said Ron Eagle, SCEA speaker, on the US PlayStation blog.
"To be clear, there is nothing wrong or causing a delay to the development of the title. We (SCEA) had to look at the [autumn] calendar with SOCOM, LittleBigPlanet, MotorStorm: Pacific Rift, Resistance 2, plus some PSN titles and make a decision where each game should come out."
Mr. Eagle also revealed that there will be plenty more information to share on Killzone 2 in the "coming months", presumably at the E3 Media & Business Summit this summer.
"The [PlayStation Day] event was the first of many steps, but please rest assured that multiplayer, co-op, story weapons, etc. will be covered in the many steps to come," added Eagle.
That full PlayStation Day Killzone 2 trailer can be found now on Eurogamer TV.
Head over to our Killzone 2 gamepage for our very recent hands-on with the PS3 flagship shooter.