R.F.
I don't know about believe in it, but it is harmless fun to read horoscopes and compare them to your personality. Some people plan their lives around Astrology, but lots of people go overboard on various things anyway - at least Astrology is safe. I am a gemini, and I can totally relate to the 'twin' aspect of the profile, as can the other geminis in my life -a very good friend, and my husband. It will be interesting to see if our daughter fits it as well!
In regards to the comment about Mercury - it's similar to noticing people being weird during a full moon. And, if I recall correctly, women used to base their menstrual cycles on the lunar phases before there were calendars (who DOESN'T act different around their period!). I think there's truth in that!
So, if it interests you, there are plenty of resources to read up on!