I actually agree also that is a wonderful rule. Here's why:

1. Places like www.cgsociety.org look a lot more professional. Why? Because some 10 year old didn't find the bigger boobs morph on his V3/V4 and wish to show it to us, in 90% of the posted images. I can understand artistic nudity, but Renderosity has become primarily a place to show off objectified and unrealistically proportioned women to the world.

2. As someone aspiring to become an artist at this, I prefer to be able to scan through Rosity during my lunch hour, trying to find images that catch my eye, that I can learn from, without fear of a coworker seeing something and it becoming an HR issue, or a rumourmill.

3. Just grow up. It's a thumbnail. So you can't show boobies. Oh boo hoos.