Its a web site, if you are at all self conscious about your looks don't post your photo there. They are BRUTAL. You have been warned.
My photos usually go from 7 to 9 in ratings, with most around 7.8 - 8.5. Which considering how savage people are there, is a very good score.
The more cleavage you show, if you have a nice figure and face, the higher the rating, which is logical since considering the name of the site.