Back in July 2004 I wrote a post Do it in your own back yard which was my initial reflection on a discussion about the use of comments in weblogs. In short I was persuaded, over dinner, by Mark Bernstein that comments were evil.
The long and short of it is this:
It's relatively easy to come to my house in the dead of night and daub "Matt Mower is a total asshole" in bright yellow paint on my (or my neighbours) walls for everyone to see, but you must truly believe it to paint "Matt Mower is a total asshole" on YOUR own walls!
Your comments should be in your own space where they can be properly attributed to you and you have to live with them. Services like Technorati make this possible. The hump a lot of us will probably have to get over is the crack-like pleasure the immediacy of comments can give. The less comments you get, the more precious they may seem.
(And please don't comment on this post!)
Update: Further discussion here.