WHAT HAPPENS ON 21/12/2012

So what is supposed to happen on this magical date of December 21, 2012

One theory suggests that a Magnetic Field shift will occur around this time, that the calendar was based on pole shifts, which have occurred repetitively throughout the Earths history. The Maya, understanding the time periods between these shifts created their Long count calendar around them and come up with the final date for the next pole shift. But how would they know what to look for to expect another shift? How much time was supposed to pass between these shifts and how did they know it? Was there record passed down to them from long ago recounting a time when there was a prior pole shift so that mathematics could be used to predict the next one to come? Or did the ancients study a form of dendrochronology the study of climate changes by looking at tree rings. Others suggest a much more mythical or religious approach. December 21, 2012 is also the Winter Solstice, and provides us with a view that will not be seen again in any of our lifetimes. The Sun will conjunct the intersection of the Milky Way in the ecliptic, giving us view of the Sacred Tree as called by the Maya, giving us view of the Tree of Life. 
Both of these scenarios are quite possible, one scientific explanation, and one religious. What we still do not know, and probably will not know is what will happen after this end date until it actually occurs. A new dawn of enlightenment would be a step towards progression, in that mankind would become more aware of their surroundings and the impact that they have on the Earth as well as a higher intelligence and consciousness and a better mindset for helping their fellow man. Perhaps this is the end, when Mother Nature finally decides to shrug off the oppressiveness that has been created by the children and start anew. 
We may just end up living through another doomsday prophecy, going to work or school as usual, looking back on the prophecies and laughing them off. Peter may have cried wolf too often for our cynical minds.