What's there to discuss, other than people's gullibility and inability to perform simple research and reasoning?
The Mayan calender doesn't end on December 21, 2012. The cycle of that particular portion of the calender reaches it's "end" and starts all over again at the beginning of the cycle. There are larger cycles on the Mayan calender that don't "end" anywhere in the near future, yet people conveniently ignore that facet of the Mayan calender. They also ignore the fact that there are smaller cycles of the Mayan calender that have "ended" several times over, and the world hasn't ended with it.
And they ignore the fact that the Mayans didn't even see small pox coming across the ocean to ravage their population and kill them off. What makes them so capable of predicting the end of the world if they can't even predict the end of their civilization?
tl;dr: there is nothing to discuss :/