I saw this documentary a couple weeks ago on the history channel about 2012.
It wasn't just the Mayan's, there is some ancient Chinese calendar that also predicts the end to be Dec 21, 2012.
The Hopi Indians believe that the world will be created and destroyed 4 times and that our time now is time number 4. They also believe the end to come Dec 21 2012.
There were some other tribes, but I can't name their names right now.
They also got into this polar shift thing too. If a polar shift occurs it's going to be a wild ride. According to the scientists before the last polar shift Alaska sat on the equator. That would mean that the earth will actually spin. I imagine somewhat in the same way my grandpa's old dashboard compass used to spin when making a turn.
Pretty scary thought, but we've had a good run. We've way over populated, killed off many species, and pretty much polluted the earth into a toxic ball of crap. It's our time to go.