Online medical reviews are becoming a mainstay in choosing a doctor nowadays. This article gives a great summary of the ideas behind it and the process.
Personally, I agree with the author. It is hard to completely trust these reviews, given that I know many good doctors with bad reviews and vice versa. Often the happy patient is unwilling to take time to write good words about their doctor, but the unhappy patient is more than willing to search out multiple sites to badmouth. I encourage patients to be honest and welcome all reviews.