The Mayans 'predicted' the end of the world. It's just cool that those dates add up to that one because of all the deaths being somewhat related to the world ending.
It was never predicted. It's just like the Y2K thing, I also believe there was some thing that happened in the 70's or 80's where the planets all aligned and everyone was freaking out saying the world is going to end. But its just urban legends, no proof the world will end that day, the only reason is because the Mayan calendar ends that day, but like I said before it is just resetting itself. It's just like we make a calendar for each year, our years ends December 31 every year it does that, the Mayans just happens to reset every 5,000 years. They must have had more time on their hands. But they were also a very smart tribe, because even today they predict the planets aligning and everything of that nature.