According to a local renown Buddhist master, this catastrophic event is really possible and can happen in a flash but nobody knows when it will happen. The 2012 date is just a prediction. But he also said that in 2012, many disasters will happen due to the reduction of the Earth's magnetic force and also the hole in the ozone layer
According to a book called Gaia Project 2012 written by a deceased Korean phD, many people would die by the end of 2009, due to unknown diseases, war, riots, massive suicides, disputes and some other crappy stuff. And then the Earth will take 2 years to go through the disaster phases: in the years 2010 to 2011. So basically, what you see happening in the 2012 movie will span 2 years, and will not happen that quickly. And then at the end of 2011, everyone is gonna die and the Earth will "dematerialize". OK, now it is already 2010 and I can see so many people in the world who are still alive. But then again, he did not say which calendar to follow. If we are talking Lunar Calendar or Fengshui Solar Calendar, 2010 starts around February 4, 2010 of the Gregorian Calendar, so we still got 1 month left. (from the time I am typing this). Just wait and see if shit happens...
Here's the 2012 Nostradamus prediction:
And here's the Mayan 2012 Doomsday prediction: