Nasa has just confirmed that something will indeed happen on Dec.21 2012.
It will start late evening tommorow here in the USA. Starting at around 6-7PM EST, we will experience complete darkness.
They also urge everyone to stay indoors and remain calm as they expect the event to only last 10-12 hours.
Its a phenomenon they have been reluctant to admit until now as they were unsure how the public would react.