Despite all the hype -- these claims are pure fiction.
The Maya calendar system is actually made out of three different calendars which were used simultaneously and synchronized before the Spanish Conquest.
The North American calendar system, the Gregorian calendar, is much simpler. Of the three Maya calendar systems, one of them is called a Long-Count calendar -- which is the centre of the 2012 "doomsday" issue.
When the counter comes to an end on December 20th some have misintrepreted it as the end of the world.
In reality, only a single piece of Maya text survived history, and it has the date December 21st, 2012 inscribed on it.
In November 2011, two scholars did a renewed interpretation of the text on the monument, and found that it states the end of an era and the beginning of a new one, and not the end of the world.