Why are people keep talking abut 2012?

Answer 1

The notion that 2012 is significant (because the Mayan calendar's "long count" resets in December of 2012, an event that happens every 5000 years or so) has been around for at least 20 years; I can remember seeing references to it in the 1980s. However, there's no actual scientific evidence that anything particularly spectacular will happen in 2012; it's no more significant than the odometer in your car rolling over back to all 0s (arguably it's less significant: after all, did you even know the Mayans HAD a calendar, or what today's "long count" is?)
Most likely the recent attention it's getting is partly due to the upcoming movie and partly due to the fact that the internet has made it trivially easy for people to spread all sorts of nonsense to the entire world.