I found out just recently that in the bible it states 'Man will not know the date' (paraphrased, and in the context of the end of the world), which makes all those end of the world types really silly..
Or maybe they're actually the smartest? By predicting the end on a certain date they're actually making sure that the world doesn't end... I think that's an excellent idea, and I'm proposing we all pick a date, if we cover every date we're safe (at least from supernatural oblivion).
So I predict that the world will end on March 17th 2009.