Pros: They encourage debate. They let people speak while hiding.
Cons: While a journalist has to tack their name to a story, an anonymous comment can remain hidden.
As a journalist, I hate anonymous comments. I personally think it's unfair to have my work ripped apart by people who won't even name themselves. Cowards. Some editors have spoken up for them, though.
However, I do see that for very limited reasons, some people need to stay anonymous. Sometimes those people can add something to the debate. It's the people who have no constructive criticism and simply want to complain for the sake of complaining. Somebody is angry about something, and they can say it because they're not held accountable.
It's unfair, but it's the route I've chosen to go at The Daily Athenaeum. We have unfiltered, anonymous comments every day. Why? Because there is that small chance of getting a news tip from somebody who couldn't reveal themselves.
Is it worth it? Not yet. Will we continue to use unfiltered, anonymous comments? Maybe not. But, it has definitely forced me to deal with the negativity of people. We do delete the comments containing profanity or ones where commenters just yell back and forth at each other.
But if someone comments that I wrote a terrible article, I should fail school and they hope I die ... it stays.
Many newspapers are changing this, though. The Charleston Daily Mail has a wall, and all comments are filtered before approval. They say:
"NOTICE TO ALL USERS:We value your comments, but we're changing the way we allow comments to be posted on our site. Rather than allowing comments to flow onto the site unfiltered, we are going to check the comments first for approval. So, readers who use the comments function may experience a lag before actually seeing the comment on our site. Personal attacks, remarks in poor taste or those overly critical will not be published. We believe the result will be a more thoughtful, civil website."
Readers hate this, but it seems to be the trend. This is eventually where I'd like to see The Daily Athenaeum go. But for now, I think it makes us more transparent, which is key to any newspaper or media outlet. I also allow anonymous comments on my blog, simply because it encourages debate and hosts that open forum for discussion.
Some other helpful links on the topic: