Is the Imdb rating scale *beep*?

As many of you may know, Imdb doesn't rate movies according to only the user votes. If it did, this movie would be rated 7.7. Instead, Imdb gives movies a "weighted average" based heavily on additional factors which they refuse to disclose. This seems entirely unfair to many filmmakers, whose praised films end up with low user ratings because of some odd, possibly illogical scoring method. I understand the basis for this kind of scoring, and its secrecy. It's to prevent users from voting for a single film many times using various user names. But like I said, it seems like it may often be unfair. If anyone knows any more about this scoring, please give me some insight. Thanks.