I think people have mentioned coComment.com as a comment tracking tool. I tried to try it but just couldn’t get it to work with my browser and just felt irky about it. Luckily there is this great one calledco.mments.com. It is simpler easier, and well doesn’t have that irky feeling around it. It has been working great on blogger, wordpress and movable type. It is easy to use and looks great too.