To those who've heard of the December 21st, 2012 prediction...?

I can tell you with absolute certainty one thing that WILL happen on 21 Dec. 2012. The positions of the sun and earth will be such that if you look towards the rising sun, you will be looking at the exact center of the milky way galaxy. The last time this specific alignment occurred was: you guessed it: the day on which the Mayan long count calender started. It doesn't represent the end of the world, it represents the restart of the cycle of the long count calendar.