Just thought of letting you know. I have the game, and the SP is extremely GOOD. I wanna tell you all to avoid reading/viewing/watching any sorts of Killzone 2 media until you get the game. DO NOT SPOIL THE AWESOMENESS THAT'S WAITING FOR YOU.
I know someone who got so angry because he was watching a YouTube impression video that doesn't even have game footage, but in the comments section he read something that ruined everything for him 100%... So you never know how a spoiler can reach you... Best thing is to stay away from anything Killzone for the upcoming days until you get the game. Hope you all get it soon enough.