It is a distinct possibility that the poles of the Earth are in the process of shifting. Should this occur, the North Pole becomes the South Pole, and vice versa. The effect is a complete reorganization of the magnetic field of the planet. Many argue this will upset the lava core inside the planet, assuming the core is magnetically responsive, causing extensive planetary calamity. In reality, we have no idea if it will do that; and we have no real idea what it will do. When the last pole shift occurred remains unknown and best guesses are indeed speculative.
Certainly, there will be atmospheric disturbances causing anomalistic weather for quite sometime. Compasses will run amuck until the magnetism stabilizes. Airport runways will require renumbering. Airplanes in flight will need to rely upon satellites to stay on course while this happens. Beyond this, we have no real good idea what will occur.
Some write of the pole shift as if it implies a tilt of the Earth's axis. Should the axis of the Earth radically shift, we would be in grave trouble. This is not implied nor likely during a magnetic pole shift. Actually the axis of the Earth recently did shift. After the earthquake of 26 December 2004, the North Pole of the Earth moved about one inch!
When the poles of the Earth shift, we should experience some discomforts, largely climatic. Weather should be fun to watch for quite a while. Perhaps individuals with strongly cultivated auric fields, regular meditators and those sensitive to vibrations will feel the effects more than most people. But it will not be the End of the World.