I learned from talking to people about Peak Oil that the whole Y2K thing hurt our society in a way I wouldn't have imagined. Y2K disaster scenarios were over-hyped and then not much happened, and it conditioned people to think that any scary prediction is probably just another false alarm. Oddly, society might actually have been better off in the long run if Y2K had either never been talked about, or if it had caused widespread, severe problems, because then people might take Peak Oil more seriously.
Looking back at World Without Oil, I think it is the most amazing, best multiplayer "game" I have experienced. Usually gaming takes time away from accomplishing useful things in real life, but WWO taught me a lot, lowered my electric bill, and got me focused on doing things that matter to me.