There were numerous press reports generated in March of 1996 on the eve of the release of new HST images of Pluto. Since then this "issue" has flared up numerous times in the media (but NOT generally within the scientific community). This situation changed in August 2006 during the International Astronomical Union meeting in Prague. Much of the popular discussion seems to be more concerned with the status Pluto. Under the new resolution passed by the IAU, they claim Pluto is to be called a "dwarf planet". Will this resolution eliminate the controversy and discussion? No. Whatever happens in the future you can still call Pluto a planet and if you forget to include the word "dwarf" I won't mind at all.
If you want to see what I think a planet is, click the link at the top of the page. I've also provided some information on the IAU resolution and the difficulties that I have with their resolution. Someday I hope we can all get back to wondering about Pluto and the other exciting new places in the outer solar system.
In the end, these definitions are useful only if they provide useful labels that collect objects of similar properties together. Trying to "demote" Pluto and rewrite the textbooks to go back to the good old days of only 8 planets just isn't going to work. The solar system is far more complex and interesting to be constrained by the new IAU resolution and future studies will help bring out the ultimate truth.
Marc W. Buie, Southwest Research Institute, September 2006