Call me stupid, but I think a lot of the responsibility falls on the shoulders of the artists who post images. One of my pictures in the beginners gallery got a comment that, in essence, amounted to "this sucks." After I cooled off, I IMd the person who made the comment, thanked him or her for taking the time to look at my picture and comment, and said that what I really needed was the reasons why the image sucked so that I could improve it. My critic not only removed the original comment, but also left me lots of constructive ideas. In other words, I took the responsibility for getting what I genuinely neeed instead of having just a knee-jerk reaction. In fact, the whole problem was more one of miscommunication than nastiness, but I wouldn't have known that without asking. The difficulties inherent in communicating in the gallery comments is one of the reasons I'd like to see us have a critique forum, or at least some kind of better mechanism for getting valid critiques.