Welcome to the world of the Halo-killer!!!!
If Killzone was a Xbox game, I am sure the reviews would be more more enthusiastic.
Killzone rules, Man! That is it.
You have a clear story, varied characters, astonishing graphics and sound. The only thing that lacks in Killzone is a millionaire release marketing campaign. It is wasn't for that, Halo would never reach the 3 (or the Zero) and the idea of a senseless FPS would be banished from the world.
Get a taste of the best European game I have ever seen: go get Killzone!