What porn pictures? and more importantly where?
If you mean the Beautiful Women's thread, it has a no nekki ladies policy, and that is kept to as Franky-sama regularly checks it out (its his job as Admin here not cause he likes doing it *cough*).
The Ecchi Sig's and Avatar's are just real smexy looking and it would be a shame to ban those.
Also when using Photobucket (which majority of users do) all 'porn' images are deleted as Photobucket will not host them.
Any other porn or such smut you should let someone from the rainbow gang know, they will take them down and punish the culprit.