According to a member of the GameTrailers Forum, someone over at NEOGAF learned that Killzone 2 will take about 45/50 minutes to complete each level. To quote:
"I saw Playr this morning too. It's basically the new version of Gamer TV. Made by the same people with the same format but with a different, less nasally, presenter. Airs in the UK on Bravo at the weekend (a satellite/cable channel).
They had a Sony rep demoing KZ2. He spoke about AI advancements although it wasn't abundantly clear that the clips tallied with what he was saying.
Couple of other things though. The dude said there were some new weapons that people would be impressed with. He then cryptically added that we'd see them in the next couple of months. Magazine exclusive reveal or more likely E3?
He also said every level would take about 45/50 minutes to complete"
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