I believe that it will just be another day. The Mayans though smart didn't are not prophets IMO, being a Christian the book says that no man will no the day and time, though I guess that leaves arguable room for men, women, children etc. if people wish to interpret things in multiple ways lol. Also, the current calendar we are on does not line up with the Mayan calendar, because our time table was not built upon theres and we have leap years. Therefore, as some believe we have already passed this predicted day as set forth by the Mayans. Nostradamus' prediction was also open to interpretation if I'm not mistaken, kind of a one prophecy fits all things within reasonable explanation type of deal lol.
Furthermore, the Mayan calendar doesn't really predict catastrophic events, but just says that it is the end of a cycle and that a new one will start. Apparently there have been multiple cycles and this is no different lol.
Now with that said, I do think there are some nuts that just might try and make something happen, but that is neither here nor there.
Would you welcome a world changing event that caused us to sacrifice something such as technology, kinetic/potential energy in currently used resources, etc. which caused man-kind to rethink how we interact with each other?