Last time I analysed revenue from ads per visitor the figure was between 0.0025 and 0.004, so 1000 views means 2.5 dollars at the low end or 4 dollars at the high end, so maybe the problem is limited to social networking sites alone. How can they make money? Perhaps freemium is the best way? I mean these people, well some of them, well most of them are addicted to Facebook and all the rubbish in it such as quizzes and friend poking, so if it costs say £2 to I don't know, send your friend the perfect girl questionnaire, sure some people will pay and if it goes hot and viral then all of them will pay, they have to.