Is there a actually a new planet?

Answer 1

In our solar system? No. There are only the eight planets. But beyond our solar system, orbiting other stars, we have found several thousand worlds. Most of the exoplanets (planets orbiting other stars) are large gas giants orbiting close, because those are what is easiest to find. But the Kepler Mission has discovered nearly half the new known worlds in just the past year and a half, and is closing in on earth sized planets orbiting in the habitable zone.

There ARE new "dwarf" planets recently discovered in our solar system. The asteroid Ceres has been known for more than a century, but Pluto coorbits the sun with another dwarf, Charon. Beyond Pluto there is Eris, which is even bigger than Pluto, and a few other bodies large enough gravity has pulled them into a spherical shape.