->Also, this isn't the first time we've thought the world was going to end, remember Y2K?
Y2K actually occurred (not in an end of the world sense mind you, but a restart or mass fix of all storage mediums sense).
->The Year 2000 problem (also known as the Y2K problem, the millennium bug, the Y2K bug, or simply Y2K) was a problem for both digital (computer-related) and non-digital documentation and data storage situations which resulted from the practice of abbreviating a four-digit year to two digits.
http://en.wikipedia.org/wiki/Year_2000_problem
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People look at things and try to draw connections. It's part of our abstract way of thinking. This can help us solve problems, but it can also be a double edged sword (people will look for connections that aren't actually there). Just because a potato chip looks like a dollar bill doesn't mean crap ; P. It just means a potato chip happens to look like a dollar bill ; ).
Mayan prediction and so on just aren't credible. The bible isn't credible either... a lot of predictions people perceive weren't even predictions to begin with (it might be random art). There's a great show called Kino's Journey where a writer writes a super sad poem in one town and its treated as a piece of work that predicts the end of the world in another. Wars spring, people go crazy, and etc. Kino's Journey really deals with a lot of fun "what if" topics and places popular beliefs of current modern society in those shows to show how crazy some of them really can be.
If a mentally ill person wrote a document 3000 years ago that talks about vague imagery and so on that can be related to the end of the world, how are people to know it was written by a crazy person 3000 years later?
Anyways, those are my own takes.