I'd have to agree with Racer X: people often form opinions based either on the opinions of others or on information that is incomplete or inaccurate.

It's really too bad that sometimes, there just isn't a way to get the information you need to really form a definitive opinion one way or the other. In those cases, I have what I'd call a 'preliminary opinion': I've decided how I feel about a subject, but it's rarely with any real conviction. Rather, I'm simply waiting for more facts to present themselves.