it's okay, but there's an actual rating system on there and people get just mean and nasty. i
''m not sure if it's still like that because i haven't been on the site in the better part of a year.

For me the main reason is community building - meeting people, sharing art, ideas, communication. Feedback is part of that but I see the larger picture of joining and/or building a community and making a genuine contribution to it as the main reason that I'm active on these sites.