Pluto is no longer a planet

Just in case you didn’t see the news today, the Solar System now has only 8 planets. That’s right; Pluto has been taken off the list of planets by the International Astronomical Union. It seems Pluto didn’t meet the new guidelines for planets. How can they do that? I mean, just like that I wake up one fine day and find that my concept of the Universe is wrong. Now I have to go back and change all my Science/Astronomy basics. That’s too much of a change to get used to. Now when any kid in the family tests my knowledge by asking me this question, I have to remember not to jump up and say 9. I am also curious how this will effect astrology. Isn't astrology dependant on the planets at some level? Will astrologers have to change their concepts too? Interesting, very interesting.