I'm no Maya expert, but so far as I understand it, it is fairly accepted that the Maya long count calendar (there are more than one type of calendar) ends in 2012. However, the Maya had a cyclical rather than linear view of time, and their calendars were circular not linear, so this would just be considered an end of one age and a beginning of another. Sort of like we think of the millenium. The Maya archaeologists I know think that people's misunderstanding of the Maya calendar "ending" in 2012 is mostly due to that cultural difference in how time is perceived. If you don't buy into a linear concept of time, there is no "end."