Thanks ICM for your response and also to Thandaluz.

It is heartening to know that artists can contact the moderators with any concerns they might have, however, this is ultimately their choice, as is their choice on whether to receive comments and ratings.

The concern raised is not over their choice to accept comments and/or ratings but how people respond to the artists wishes, that is really the heart of this thread. I know that people react differently to criticism but I've have known people on Renderosity who have been deeply upset by vicious comments and as a result have stopped posting for a while. One artist in particular received an awful comment and others 'jumped on the bandwagon' and joined in the crucifixion of the image. To be fair this artist gave as good as he/she got but people were amazed that this type of thing could happen on here.