Again this just comes back to what I consider IMHO to be the simplest, easiest to implement, least contentious way of handling the situation.

Have a nudity flag and set it off by default. If somebody wants to view images containing nudity then they must conciously check the nudity flag and save their profile. Purely by the nature of this choice people cannot complain that they are not getting what they asked for. When someone who has not enabled the nudity flag browses the gallery, quite simply do not show any images or thumbnails that contain nudity!

This argument of 'I want to view nudity, but only if it's tasteful' isn't very strong IMHO. If someone willfully and knowingly chooses to view images containing nudity then they must be prepared to get what they asked for! They have effectively chosen to be their own censors, so why should they be given the opportunity to complain bitterly that they wanted nudity but 'not that kind of nudity'.

If someone is browsing the Renderosity galleries from work but is concerned that they may see 'inappropriate' content then they can simply switch off the nudity flag and never have to worry again! How much simpler than this can it be?

To sum up, as has been mentioned in this thread and elsewhere, rules should be simple, effective, easy to implement, and not rely on subjectivity to be enforced. What I have proposed here has been voiced by many many others and it fits the bill quite nicely don't you think?

As per usual, my 5c-worth. I'm now wearing my asbestos suit so let the flaming begin! :)