To be honest, my OCD and severe anxiety issues had me worrying about this all throughout this past summer, all because I got on Facebook and a friend of mine posted that he'd be "Attending the Year 2013." I saw that and that was just it; I couldn't stop thinking about it. But now I see that for the petty lie it is and don't worry about it. Besides, even if the end of the world does come to pass, why does that matter? Each individual's world ends on the day of their death and that could be anytime, anyway.
Interestingly enough, I read somewhere just yesterday that the Mayan Calendar doesn't count for leap year and that, if it did, the date of the end of the world was calculated to have actually been, like, seven months ago or something. But I don't know exactly how that works; seems iffy. Leap year adds days, so...? I dunno; the article seemed strange and shady. But whateverrr.