its codwallop... IMO.
People (yes i am generalising here so obviously not everyone) need something to believe in. They cant accept that day to day life in not controlled but some huge outside force and so they create a means by which to explian why this happen the way they do... if you were born in march you are sad today cause the moon is up uranus, etc. I place astrology in much the same boat as any religion, and infact if you look at it they are not too dissimilar are they? they all look for some external force to explain how things happen.
er... i'll just lower my horned head, tuck my spiked tail between my goat-like legs and go and sit facing the corner now