When uncertainty clouds an issue such as the future, you may apply reason to attempt a logical conclusion to events.
No one knows what will happen in 2012.
Some believe the world will end. Their beliefs are not based on facts.
Using the philosophy of preordained destiny, we know that when people believe something is going to happen, they subconsciously enact steps necessary to ensure the event will happen.
So!
In 2012, most likely noting will happen; however, because of people's strong beliefs that catastrophic events will occur at that time, they will mentally carry-forth with those beliefs. There will be mild but un-pandemic panic leading up to the date of supposed cataclysm, somewhat of a endemic view (I'm thinking much more than Y2K), but afterward an extreme self-ridicule when the general populas realizes that a date is...just a date