How far in advance do they film? They haven't shot the whole season yet?
Keifer was on Charlie Rose's show last week and he said that the writers haven't finished....that is why it is so hard to predict....just when you think you know where the show is heading, they surprise you.
They are still shooting and will at times incorporate recent news headlines into script or at least they have in the past IIRC. I think 9/11 caused them to change the script in the first season. From what I understand they are a little over half way done when they air the first episode.