Killzone 2 levels to take 45-50 mins to complete?

Playr, an updated version of GamerTV on Bravo in the UK, recently hosted an episode where a Sony representative played and talked about the highly anticipated shooter, Killzone 2. On the show, the rep spoke about a number of things including AI, weapons and the like.
The one thing that caught our attention was the mention of “45 to 50 minute levels.” With such massive levels could come some truly unforgettable experiences. This, however, begs the question, how many levels will be present in the final game? We personally don’t want five or six hour-long levels in lieu of thirty fifteen minute levels.
While we check our math, you can voice your opinion on the matter in our comment section. Would you rather have fewer, longer levels or shorter, more plentiful levels? [PSU]