"Does Earth have a new friend? An astrophysicist says it's likely that an as-yet undiscovered planet exists on the dark fringes of our solar system, messing with the orbits of celestial bodies in the Kuiper Belt, just beyond Neptune. Rodney Gomes says the new planet could be anywhere from half to four times the size of Earth and is likely a rogue planet that floated over from another solar system. Other space scientists say Gomes' findings may be a lot of hot air and aren't sure his calculations support his theory. Buzzkills. We already lost Pluto. Stop playing with our hearts. Give us the new guy."
http://now.msn.com/living/0514-secret-p ... nowcontrol [Edit: fixed URL link]
I'm not fully versed on the subject of the Planet Nibiru thing, but does this possibly vindicate some of the therories/studies proposed by Zacharia Sitchin? Quite Literally, Sitchin proposed that there is a planet called Nibiru just beyond Neptune where a race of extraterrestrials maintain a presence.