Is it ethical to remain silent when you are seeing, with your own eyes, a case of cyber-bullying?

Are you talking about cyber-bullying, or just breaking the community guideline rules on YA? I think bullying should definitely be reported, but I've noticed that many times on YA you'll get reported just because what you've said has struck a nerve and someone doesn't like it. YA rules are, for the most part, just politically correct silliness. Adults should be able to communicate without worrying about their comments being deleted just because someone disagrees with them. Another thing I've noticed that makes no sense at all, is that when a person is reported for an obscene avatar their comment is deleted, but the offensive picture isn't removed. That accomplishes nothing. You are one of the very few people who can always be counted on to offer fair, well thought out, sensible comments, and I always enjoy reading what you post. More of us should follow your example.