It's supposed to be a long term thing. Meaning, 2013 is the year things start going boom. The earth is going to be hit by a barrage of solar flares in 2013 when the sun's magnetic energy cycle coincides with its 11-year peak in super-powered-sunspot activity. And that's not me making this up, NASA said the same thing. The flares are supposed to change the magnetic field of our planet and systems will not work and stuff. They know it's coming, they just don't know how bad it will be.
I've also heard something, like, the North and South poles are going to very suddenly shift in a matter of seconds, which is going to send the world spinning like a frisbee causing earthquakes and tidal waves over the whole planet.
All in all, there's so many theories about 2012/2013, pretty much anything can happen. I for one do believe that something (bad) will indeed happen.
Poll