Dude I despise that film. It is so unbearably Hollywood. It isn't even risky, it is desperate for a reaction. I love Fincher and I think he deserved best director this year for the masterpiece Social Network. This is a film I try to block out of my head. It doesn't stick with me in a chilling way, but I just can't forget how brutal of an experience it was sitting through the catastrophe. The fact people love it so much makes me sad.
I think that the seven deadly sins part of it could have been very philosophical, but the villain didn't look motivated at all. Spacey was more of a screwed up extremist than a person with a strong emotional motivation. Fuck this movie to hell.
The answer to all the madness of the "Final Destination" saga (someone finally answered the same question i was wondering lol) is this: its cause death wants the person who sees the visions in the movies to die, the other people are just fun on the side. The person has a choice either let everyone who was in the accident die before him/her or choose to die before death kills everyone else cause once the vision person dies, the others are safe unless they intervene with a person's death then they are back in the game.