Why are facebook and myspace worth so much? How do they make money off advertising?

[J S]

How are companies like facebook and mayspace worth so much money, how do they generate revenue?

[Mark M]

To be honest, Facebook isn't really generating much revenue yet. They're still fleshing out their advertising model. Myspace, on the other hand, has had a pretty good advertising setup for a while.The value is in the users. Tens of millions of faces to potentially advertise and/or get polling data from. A lot of the worth is in potential that is untapped. Some of the worth is in hype.