I'll make a quick comment, then I'd like to hear the other witnesses' thoughts on this same issue.
We often raise the potential problems of censorship. I think most people would agree there would be problems with censorship certainly around preventing adults from accessing this material, but I know that the British government has tried to explore ways of at least preventing young children from accessing hard-core, violent sexual images. It seems to me you'd have to be a pretty hard-core free-speech libertarian to think that young children should be able to access these kinds of images without some kind of regulation, but I'd be curious to canvass the other witnesses on this as well.