A nice summary of the current state of thinking, Jason. As for the open question about whether or not we humans would change in any way if we knew about some future cataclysmic event, I suspect after the initial religious fervor, mass hysteria, and mass slaughter, things would go right back to normal. Humans are in general not very good at retaining abstract concepts but are very good at being mesmerized by social trivia. Evolution has shaped us, and no abstract far-off impending event can over-ride our inherent limited focus.