Wait, are we talking about the economics of porn producers, or porn whores?
Porn doesn't seem to be particularly lucrative job to me, even with the other financial opportunities it leads to, like licensing rubber twats or feature dancing. But most of the young women entering porn are not likely to use it as a springboard to an investment banking career. For an 18-21 year old, it's a great sum of money. And you get to be "famous" too and have lots of Myspace friends and buy a Humvee - yay!
It's a market subject to the laws of supply and demand like any other, so I assume rates are exactly where they should be. When I see a whore who is truly beautiful, however, like Aurora Snow, for example, I wonder if she knows the opportunity cost she forked over by not working at a high-end Manhattan escort agency, where she could have been pulling in $1000 an hour minimum, plus tips, plus gifts. Even with the agency's cut, it's a better economic proposition. But maybe she and others prefer the certainty of working with those that they already know, and the whole fame angle. I dunno.