That's right, no silly tins, no crappy helmets taking up space on your shelf for the rest of eternity. Sony's Jeff Rubenstein confirmed in a comment on the official Sony blog that there will only be one version of Killzone 2:
There is no collector’s edition slated for Killzone 2. Guerrilla Games has put all of their effort into creating this masterpiece of a game, so we didn’t actively pursue a CE.
It will come in a box, which will contain a Blu-Ray disc that has Killzone 2 on it. After all these years of waiting for Guerrilla's hotly anticipated first-person shooter, that's probably going to be plenty. As someone who is repeatedly suckered into buying more expensive editions of games that rarely offer enough meaningful stuff to justify the expense, you can count me as thankful. Though a big Helghast figurine might have been cool, now that I think about it...
While we're on the subject, here's an interview that Rubenstein conducted with Guerrilla's Hermen Hulst during CES last week: