You can't rate the rater's because that's all subjective. This is where a nice machine learning algorithm that looks at your scores and find people who have similar rating trends. It would then give weight to other peoples ratings based on your ratings.

Thus is born a system in which everyone is happy. The site will get more ratings because people want the algorithm to be better and it needs more data for that.

The movies will be happy because this points to legal ways to find movies.

We'll all be happy because it's a complex solution to a complex problem and yet it can still be solved in an elegant and visually stimulating way. (I.E. you could color code the reviewers who are more likely to be similar to yours)