On the 21st of December too many people will post on facebook and twitter that they are still alive and the earth has not been destroyed. This extreme strain on data traffic however, will paralyze servers. Financial traffic, stock exchange and news media will stop to function and a worldwide panic will follow. North Korea will use this opportunity (since their people are not allowed to use the Internet, they will have little problems with crashed servers) to try and take over the world, which will shortly be answered by the west with nuclear retaliation, resulting in Armageddon.
Now whatever you think will happen the 21st.
CALM THE FUCK DOWN!
Oh and merry x-mass, peace on earth and all that crap.