by Mark van Stone, FAMSI (Foundation for the Advancement of Mesoamerican Studies Inc.)
This is the most definitive article on the subject I have seen.
"Maya Scholars, in Mexico, Guatemala, Belize, Honduras, El Salvador and North America, have been watching with amusement and dismay as self-styled experts proclaim that ancient Maya prophets foretold an earth-shattering happening to occur December 21, 2012. This predicted phenomenon gets described in contradictory but often cataclysmic fashion -- as an ecological collapse, a sunspot storm, a rare cosmic conjunction of the earth, sun, and the galactic center, a new and awesome stage of our evolution, and even a sudden reversal of the Earth's magnetic field which will erase all our computer drives. One even predicts the earth's initiation into a Galactic Federation, whose elders have been accelerating our evolution with a 'galactic beam' for the last 5000 years. In sum, the world as we know it will suddenly come to a screeching halt."
"These predictions are alleged to be prophecies by so-called 'Ancient Mayans' whose 'astronomically precise' calendar supposedly terminates on that date. According to such accounts, these mysterious Maya geniuses appeared suddenly, built an extraordinary civilization, designed in it clues for us, and then suddenly, inexplicably, vanished, as if they had completed their terrestrial mission. These same experts claim special credibility for the Maya prophecies by asserting that these historic sages, with their possible extraterrestrial origins, had tapped into an astonishing esoteric wisdom."
"Could Any of This Be True?"
"The credibility of those claims deserves rational attention - which is what I intend to provide. Neither mystic nor prophet, I am a Mayanist. More specifically, I am a professional art historian and an epigrapher (less formally, a glypher), one who can read and write Maya hieroglyphs. For over a decade, I have focused my scholarly research specifically on Maya culture and writing, making some surprising discoveries that can present a more definitive perspective on the prophecies of the ancient Maya seers. As we approach the critical year, it is time to offer a more viable account of the Maya prophecy and expose both the fallacies and ethnocentricism tainting the current sensational accounts."
Lots more here :-