If There Never Were Nine Planets, My Horoscope is Skewed

From the LA Times today:

"...astronomers meeting in Prague, Czech Republic decided the rocky ball of ice on the outer edge of the solar system was too small and insubstantial to merit inclusion with the other eight planets.

"Members of the International Astronomical Union voted nearly unanimously to demote Pluto to "dwarf planet" status, a new category that also includes the large asteroid Ceres and the recently discovered Kuiper Belt object UB313."

We've known for a little while that there were either always only eight planets, or more than nine. In the same class as Pluto, there are at least 2 other heavenly bodies identified that have at least an equal significance in our system's realm of "planets."

So, why does astrology place destiny-guiding significance on Pluto, and all the while ignore these others? How can I have confidence that luck is on my side because Pluto is far from Aries, if I now know that another unknown heavenly body of equal substance as Pluto is driving right accross it?