They're now debating an official definition of what is a planet. If they accept Pluto and the latest object, it opens the door for a lot of planetoid objects they've been discovering. But there is a movement the other way, too. Pluto might become a "dwarf planet" and we go back to 8 planets, not 9. Personally, I like the idea. It's always seemed anomalous, kind of an afterthought. Which of these objects doesn't fit?
Of course, they also acknowledge that in layman's thoughts, there will probably always be 9 planets. But I still like the idea.