I found this interesting poll out recently which surveys the stance of Americans on the morality of a number of different issues, including both porn and prostitution:
http://www.angus-reid.com/wp-content/up ... ty_USA.pdf
With regards to pornography 58% say it's morally wrong while just 33% think it's morally acceptable (22% of Republicans, 34% of Democrats and 41% of Independents).
On prostitution 65% say it's morally wrong while 25% say it's morally acceptable (16% of Republicans, 28% of Democrats and 32% of Independents).
It doesn't give any breakdown on the figures for different age groups or the reasons why people feel the way they do but it's definitely good to see that the impression you often get on the internet of everyone being a rabid supporter of the sex industry is not necessarily always representative of the public as a whole.
Disappointing though that people think they're more morally acceptable than using illegal drugs or committing suicide or that people aren't that much more anti-porn than they are anti-abortion.