For the ancient Maya, it was a huge celebration to make it to the end of a whole cycle," says Sandra Noble, executive director of the Foundation for the Advancement of Mesoamerican Studies, Inc. in Crystal River, Florida. To render December 21, 2012, as a doomsday or moment of cosmic shifting, she says, is "a complete fabrication and a chance for a lot of people to cash in."
The astronomer Philip Plait has stated very clearly that the Mayan calendar does not end in 2012 at all, that it is like the odometer on your car, as each section of the odometer reaches 9 and then clicks over to 0, the next number to it starts a new cycle, so that when all the numbers again reach 0 all the way across the odometer - the last number will change from 1 to 2 and the new cycle starts all over again.
The Mayan calendar has already reset in the past and we are still here. Also the Mayans predicted things will happen using dates beyond the 2012 reset. They never thought 2012 was the end, just a new cycle.
If you really want to believe the Mayans knew something no one else has been able to figure out (I personally don't), then it is more practical to believe in some sort of change like a pole shift/switch on 2012.
