Mayans were richard-suckers to their gods
don't trust them
Nostrodamus predicted the rise of Riddler and what not. He said the world was going to end in 1999. boy was he wrong
but it almost did
millenium bug
Nostradamus made super vague predictions that were almost impossible to not occur in some way shape or form which you could later assosciate his predictions with.
It's the case of some person 500 years ago saying "In the future a tower will fall and many will be hurt", and then us saying that he predicted 9/11, despite the fact that Towers fall all the loving time and are never going to remain forever, and when towers fall, it's very likely for someone to get hurt if nearby.
I think it got a load of hype for whatever obviously fake reasons, but then it became well spread and a popular idea and has influenced many things in the last few years.
We've had movies and games and books and songs and all sorts based off of on idea. Which I think is great. I don't think the world will end this December, nor do I think many people believe it will. But I'm glad the concept of 2012 got well-spread, because it's made a nice impact on our culture for the last few years, and likely will afterwards.