That was a close one. I must admit I was a little bit worried that the Mayans had got it right. Fortunately, not only did they get their calendar wrong but, according to Pope Benedict XVI, so did the 6th century monk, Dionysius Exiguus.
Exiguus created our modern calendar which begins with the birth of Jesus Christ. But in his book, "Jesus of Nazareth: The Infancy Narratives," the Pope says that Exiguus ”made a mistake in his calculations by several years. The actual date of Jesus’ birth was several years before.”
This means that if the world ends on 21st. December 2012, then it already has. We're all safe or dead already.