This is a very worthwhile link on the 2012 silliness. It features an upcoming book, an interview with a Mayan specialist, and a link to an academic paper (but it isn’t free). The book may be quite expensive, too (Equinox titles usually are). But at least you get the interview.
Despite my enthusiasm, I expect that the new-agers or ancient astronaut theorists will make sure this good scholarly deed gets punished (or ignored).
I have added a few different presentations from Ian Lungold on 2012-Tube as I found his presentations to be the best explination of the Mayan Calender. This is a very detailed presentation and certainly worth a view if you have time.