I think people sign up expecting it to be the end-all for free models. When in fact it is kinda more like "bottom barrel". I have not had any flake on me and am happy with the ones I have worked with. But MM is not like an agency. Nobody is accountable to anybody, and reporting bad experiences can get you banned. So you have to take it for what it is... simply a social networking site that happens to be centered arround the modeling industry.
It is also the last place I would go for advice or C&C. If you read through the forums, it is mostly Photo 50.5 questions. (As apposed to Photo 101) Sure there are some good questions there. But 90% of them I would not expect from people "working in the industry".
exactly what he said..lol. I've seen some shots that would be laughed off of POTN get praise over there.