You know, I've done lots of research on the subject. I've studied ancient Mayan legends, folklore, history, and even touched on psychology and anatomy/biology to see what makes them tick. I've also gone and looked up a whole range of scientific materials on the subject from a wide range of sources. I was preparing to answer this one question all this time. But I thought my preparation was insufficient, so I dove into even more materials, which may be unconventional, but I thought could prove insightful - astrology, numerology, gnosticism, hermeticism and a few others. I even used some tools, and I'm using the term somewhat loosely here, in pursuit of an answer. Among what I tried were crystal balls, tarot cards, contacting the spirits of the dead, chanting, prayers, meditation.
So, in short, I think I am the most qualified person to answer that question. And I do have an answer. Just to reiterate - I've spent very large amount of time and effort to reach this answer and I've checked, double checked, triple checked and many-other-checked it using a wide variety of tools methods and techniques, so I am absolutely sure it is correct.
And here it is: the world will either end or not. It is a 50/50 chance. All the sources agree.
As a side note, a somewhat interesting observation - the same chance crops up for every other date I checked.