Tigershark: It's probably been said earlier, but I'll say it again: people don't post their images to get "constructive criticism", they post images to get glowing remarks. Look at any image and you'll see comments like "so cute" and "love what you've done with it" and "beautiful". If anyone so much as says, "the pose is un-natural", that person is labeled a troll for their negative comments. Most people seem to have a very thin skin and respond to negative 1 of 2 ways:

• If you don't have a gallery, you are in no position to critique other people's work. Using this logic, you may not critique the movie "X-Men" unless you yourself have made a major multi-million dollar Hollywood movie based on a comic book series. Similarly, you are also not allowed to critique a CD unless you yourself have had a recording career and know how to sing professionally.
• If you do post a negative comment that is really negative, the "artist" may get so upset that she'll post a message about how she's quitting Renderosity and no one will ever see her again. Her friends will then jump in and tell her that her images are very good, to not pay attention to that awful troll, and not to leave.