I've heard a lot of complaints about what a b*tch moderating comments turns out to be. So why not create an API for moderating comments?
Suppose your blog engine put all incoming comments in a private authenticated RSS feed. You can then subscribe to this feed and for each item, hit "YES" or "NO" via your RSS Aggregator. I'd be willing to write an IBlogThis plug-in to support such an API if someone adds it to the various blogging back-ends. If it caught on, I'd be happy to add it to RSS Bandit if Dare and Torsten like the idea and approved it.
The API would probably be similar to the CommentAPI or my RatingAPI, but with a few modifications specific to comments. I'll propose one later.