Pluto is still a planet in New Mexico because the guy that found it lived here so we're officially the stupidest state in the U.S.!!!!! Oh, the excitement is overwhelming!!!!!!!!!!!
Okay, Pluto does not meet the criteria required to become a planet--and you should have known that at the start, when the EXPERTS made the decision. -.- Also, if Pluto became a planet, Makemake, Eris and all the other shit-holes at the edge of our galaxy would become planets, and the Solar System would be like 20 planets larger.
Just to add to this--gravity is not what's happening (at least it's very unlikely)--it more likely to be a case of dark energy. Dark energy is the leading theory for the Big Freeze. Even our moon is receding from the orbit of Earth.
The reason the moon is receding from is simpler than dark energy. The Earth is rotating and as the gravity of the moon is causing the Tides on earth -As a result, some of the Earth's rotational momentum is gradually being transferred to the Moon's orbital momentum, and this causes the Moon to slowly recede from Earth at the rate of approximately 38 millimeters per year. In keeping with the conservation of angular momentum, the Earth's rotation is gradually slowing, and the Earth's day thus lengthens by about 17 microseconds every year. However the Martian Moon Phobos the tidal forces are lowering its orbit, currently at the rate of about 20 meters per century, and in 11 million years it will either impact the surface of Mars or (more likely) break up into a planetary ring