Well, according to one fellow. In amongst talk of time-travellers, stargates and "j-rods", is this:

"In 2012, the Sun will shower the earth with waves of energy, bound to the Einstein-Rosen Bridges that are clumped together at the Galactic equator." and that all of the "natural stargates" will turn on, causing "something wonderful" to happen, but that if we do not disable the manmade stargates first, the excess energy will cause the poleshift, "first magnetic, then geophysical". The result would be a minimum death-toll of 4 billion, according to Burisch.

Source: Area 51 Microbiologist Dr. Dan Burisch