End of the world. 24th December 2012?

Ok in my social science cl in school i watch a doco on the Incans, Mayans and Aztecs. I can't remember which civilisation it was. But the mathmaticians and astrologies of those days did all this working out. To do with the eclipse and stuff like that and numbers. they some how worked out that the end of the world is gonna be 10am, 24th, of December 2012. I dont know what to think bout it. What are your thoughts on this? I dont think that it is something that can be worked out by numbers. Really this isnt a question. I just wanna create a discussion on the idea. I'm wondering what everyone else is thinking. thanx :P