While making commenting easy is important, another part of "feedback" is the author's response. I have tried both moderated and unmoderated comments. Recently, I had a comment I was having trouble deleting, so turned on the moderate function until I could figure out how to delete unwanted comments (I've figured it out).

As I went back to moderating, I realized that I like the ability to see the comments so I don't miss any. Blogger allows me to moderate comments posted after so many days. So I have gone back to having unmoderated comments, but only for posts less than a week old. This means I'll be able to catch someone's comment on a posting I might have written 2 months ago.

I think it is as important that those that comment have some recognition that the feedback has been received (either in a later blog post, or on the post itself).