The mayans didn't believe in the end of time. The "Golden Age" will begin. There's an entire story about how they predicted that the sun will move between the Milky way and some other area in the sky, right in the heart of an area called the "tree of life" or tree of whatever it was called. Then, everything shall be united spiritually, and humans will move away from materialistic things, to become more in tune with nature.
At least, I've been freaking over 2012, and reading that everywhere I go has given me piece of mind.
However, it does not mean that nothing will happen to /change/ our world. We are supposed to collide with something big, and we'll probably lose 2/3 of our population. However, the world has lived through over 150,000 "disasters", and the last six, I read, happened while humans were on the planet. We obviously will survive whatever the hell happens, and it's obvious that if nothing happens, we will all appreciate a little more what we could have lost.
Whew. xD