I believe I've found incontrovertible proof the world will not end on May 21, 2011.
First, you have to understand that while the ancient Mayans were "advanced" for their time, their "prediction" of the end of the world might be subject to some small margin of error. First, their calendar ended some 400 - 600 years (approximately) in the future at the time of their production of the calendar. This is something grander than our current predictions of the doom of civilization predicted by the global warmist alarmists. After all, they're only looking out about 100 years, and merely predicting ecological catastrophe, rather than the total destruction of the earth (and perhaps the universe itself).
Secondly, since that ancient time we've made some minor, but significant, advancements in the understanding of orbital mechanics - not just of our solar system, but also of our galaxy. So our predictive models should be more accurate than those produced primarily with sticks and stones. After all, we have personal computers, calculators on our iPhones instead of our fingers, etc. So clearly we know a little more. Plus, we can shoot our arrows much higher into the sky...
Recently, I was at my local, going-out-of-business bookstore looking to score a printed book cheaper than I could get for my Kindle. Alas, no joy for me. However, I did find calendars. Hundreds of them, all produced by not just one oracle, but dozens of them. They all had similar calendars. But more importantly, THEY ALL ENDED ON THE SAME DAY - December 31, 2011!
That means the world ends January 1, 2012.
Now, we know a little more than the Mayans. And our current time is much closer to the modern predicted end of the world, so less subject to days or even weeks of marginal error. So I have faith that our modern predictions are more accurate than those of the Mayans 400 or so years ago.
So rather than party my ass off on May 20, 2011, I'm waiting until December 31, 2011. I understand others have similar plans this year ...