This board's full of specific negatives about online porn... Just do a search and make shit up:
1. Tours / advertisements that completely mis-represent the experience after the credit card has been swiped.
2. X-sales
3. Being a sponsor and working to not get constantly fucked by sketchy affiliates.
4. Being an affiliate and not get fucked by sketchy sponsors.
5. Lack of accountability; anyone can open a porn site, do what they want and get out if it's too sketchy.
6. Lack of morals; "if it makes me money, fuck the rest of you".
Maybe I missed the point, though anyone reading threads on this board for even a week could make up some shit.
Edit: Some of the people in the online porn business: i.e.
http://www.gofuckyourself.com/showthread.php?t=866650