Actually it isnt just the mayans that believe this theory, many other religions do and even scientists have found evidence supporting it.
i beileve that only GOD knows when the world will end and he isn't telling anybody..not even jesus knows..God has it written down and only he knows for sure..as far as these scientist go..i don't think they know crap..because most of them realy on there scientific knowlege and for the most part i don't think they beileve in god ,heaven ,or hell..
Food for thought http://www.youtube.com/watch?v=QJjQMwEjC1I