I turned off moderation recently when I turned on a word verification. I kept moderation for a while because of an influx of spam I had been receiving. While comment moderation does stifle some conversation, at times it is a necessary evil. When I had moderation turned on, I never rejected legitimate comments--even ones I disagreed with. It was the spam I was most worried about.

I agree with Holly: it's a spam issue.

I think you're post is right, though-- and it's the responsibility of a blogger who is interested in open discussion to approve the good, the bad, and the ugly; if for no other reason but that it adds depth to the dialogue.

After reading your responses, I see that as my little blog grows, comment moderation may be something that I'll have to implement one day in the future. Something, I had never really taking into consideration, until now.

Your openness and commitment to sharing your opinions makes the blogosphere go round. Thank you all.

Yeah, it's one of those things every blogger has to decide. I moderate comments because it makes me feel safer about whatever I'm going to say. I don't actually say stuff that's all that controversial, and I've never not approved a comment, because even people who disagree with me have been super respectful. But I think of my blog not so much as a completely open forum, but as a home where I welcome people in, reserving the right to kick them out if necessary. It might depend on what you want for your blog.