Hi,
The huge majority of all climate scientists think that global climate change is a bad thing, and many of them now know that it is worse than we originally thought. In fact, all the data show that it is accelerating much faster than was thought just a few years ago. We need to let the scientists who study the facts, make their judgments. If we want to dismiss their conclusions, or reinterpret the data, then we are being arrogant.
James Hansen, Lonnie G. Thompson, et al are not making it up.
http://livinggreenbarrie.com/LvGnGlblWarmgIPCCRpt.pdf
As far as the number of planets in the solar system -- this is the decision also made by scientists based on the facts. Pluto is smaller than other objects that we have never called a planet, and it's orbit is pretty strange -- out of the plane and some of the time it is inside Uranus, IIRC.