Greg Laden has an entry discussing whether or not to date someone who believes in astrology.

He concludes: no.

The first commenter says: "Nobody should date women who believe in astrology."

Hah. I've seen polls all over the place on this one, but I do have one interesting anecdote. When I lived in Dallas I signed up with Match.com for a while. When you're filling out your profile, for the "Astrological Sign" category, you can either put your sign or select "I don't believe in astrology".

One of the first searches I did was to search for all women in the Dallas area between the ages of 20 and 40 who had selected "I don't believe in astrology". I got less that ten hits, and the majority of those were fundamentalist Christians who didn't believe in astrology because they thought it was satanic.

Of course, there are degrees of belief. This site cites a poll which indicates that only 18.1% of women polled indicate that astrology is "Definitely Not True", which actually seems a little high based on my personal experience.

Anyway, if you're a guy looking for a girl who doesn't believe in astrology (to any degree), good luck. The odds are stacked against you.