If anything happens on 2012 it will be caused by Man, wheather its the "illuminati", or "elite", or just some psycho cult, theyll just use it as an excuse to do something.
IMHO there is no way for man to know when the end of the world will be.
Besides, the 2012 thing just means the begining of a new star era or something, not total world destruction.
Lulz.