If the theory is based on the end of the Mayan calendar, then one should look up and understand what did the end of a cycle meant to the Mayans; there are speculations that it meant re-birth, or significant change. One thing that does bother me is the fact that thousands of years ago, more than two civilization stared working on erecting monuments to the goods (seen in the Sumerian tablets, and Egyptian and Mayan pyramids) that are constructed very similar in shape and in purpose. At the time there was no means of communication, and yet we still see the edifications raised with the sole purpose to serve the Gods. Could it be that there is a connection with the "newly" found planet "x" (although the Sumerians had it inscribed in their tablets long time ago).
To my understanding the end of a cycle only means that it will repeat itself, over and over again, however, the world will be face to forego an extreme transformation in order to endure life.