There is so much that goes on these days, especially around Christmas time, where a really sarcastic "Because that's what Jesus would do." is so appropriate.
it might also be to do with the world ending... people tend to get abit more crazy when someone says the worlds ending... think of how many people comited suside before we came into the year 2000 because computers and clocks where going to stop apparently... so it might have something to do with the mayan calender ending as well ;/