Tomorrow, as many of you know, is the equinox. It is also supposedly the end of the world. This theory was derived from some fairly arcane interpretations of the Mayan calendar. I have a few problems with this idea:
1. The world survived the Late Heavy Bombardment and Chicxulub, so I fail to see how a calendar is supposed to ruin everything. It would have to be an inconveniently large and heavy calendar to do much of anything.
2. 2012 signifies the end of a long count cycle in the Mayan way, going from 12 to 13. This happens every 5,000 years or so. It's cool that we'll be around for the change over, but it seems unlikely the world will end.
3. If the Mayans were so good at predicting the future, they'd probably still be around.
4. While it's possible that the end of the long count signifies the return of the space aliens who taught the Mayans everything they knew, it seems implausible. I can't judge the motivations of space aliens, but they probably have better things to do than show up every 5,000 years and bother humanity.
There are two possibilities: either I'm right and will have to do my Christmas shopping tomorrow after all, or the guy on the street with the sign will be shrieking "I told you so".