Some of us may, either through natural causes, an accident, or in some other way. Most of us will not.
I do not believe in the Mayan theory.
Probably as many people will die through the normal course of life on this planet on December 20, December 22, as well as any other day of the year as will die on December 21, 2012.
In opening, I do not believe that the world will end on December 21st of this year. Give my curiosity, I have done some research on the "end of the world," according to the Mayan calender. Essentially, the Mayan calender ended long ago. Today's calender is very different from the Mayan's original. We currently celebrate Leap Year (which was not a part of the Mayan calender). Based off the original calender, 12-21-12 has come and gone (when looking at the original).
Bravo! Posts #1 and #2. Remember when the Y2K scare was popular? I remember where I was on New Year's Eve 1999. Everyone thought that the internet and computer systems of the world would collapse because there were problems with dates on computers going from 1999 to 1900? Everyone thought that if the dates didn't roll over to 2000 at the stroke of midnight that everything digital would crash! There were probably other rumors floating around at the time, too. But everything went just fine and no one's money was lost. The internet flourished and everything was fine. I'd be more worried about current patterns of behavior and trends (as with the economy) as guides for problems facing our world rather than an old calendar based on superstition.
In addition, they have found evidence that not even the Maya actually believed that the world was going to end this year. They've found some sort of Maya calendar that shows things happening after 2012. Not even the people who allegedly predicted this really believed it, so why should we?
That's actually the more interesting question -- why do people believe in this stuff?
The above post is exactly right. I would add that it is also a little silly to privilege one culture over another when it comes to making claims about when the world will end. There are thousands of different religions and traditions concerning the end of the world, and it is odd that popular culture should have embraced one.
I think you might want to clarify the difference between a culture dieing off and a group of people dieing off. There are certainly instances where a group of people do all die off. Some of the most notable examples I can think of have to do with early settlers. Sometimes an entire village would be wiped out. Other civilizations didn't die off but rather they joined other cultures and thus their culture died out. The Mayans did not die out. Their culture changed and grew as other people and other cultures joined their society, but there are still true Mayans today.
In reference to the Mayan calendar which ends in 2012, it does not mean the world will end. The Mayans made many different calendars. Let's face it, there's only so much you can chisel into one rock tablet. In 2012, one Mayan calendar will end and another will begin. This is a significant event in their culture but it in no way signals the end of the world. This myth has been created by those who do not understand the culture and it's implications.