The predictions of disaster in 2012 were based on superstition but are now entirely lies.
The Mayan calendar was not particularly accurate. They had a 365 day year but it is not certain that they allowed for leap years like we do. It would not matter whether their calendar was accurate or not, what matters is whether prophecies of doom are any good. And they never are. See "A Brief History of the Apocalypse" which sets out hundreds of different doomsdays that never happened.
In any case, the Mayans did not predict the end of the world. All that happens is that the current cycle of their long count of days (which is not really a calendar, just a count) will reach a round figure according to the Mayan counting system, which was not like ours. According to one of their inscriptions, one of their kings will be remembered in our 48th century. If the Mayans still had a government of their own, it would probably be party time as it was a sort of new year for them.
Everything else you have been told, read, seen on YouTube or the Hysteria Channel is lies. Stray planets, galactic or planetary line-ups, bees dying, Nostradamus, I Ching, ancient Egyptians, Hindu, Buddhist, Jewish or Christian scriptures, Bible codes, magnetic or geographic pole shifts, you name it are all lies. Most of the bunk is recycled from the ends of the world that didn't happen between 1999 and 2003.
The lies about this multiply by the month as some new fraud comes along and tries to frighten people into buying survival supplies, guns, disaster shelters, lying books, DVD or in to dangerous religious cults where they can get at all the sucker's money.
See
http://www.2012hoax.org