CoComment is an interesting service that helps you monitor comment threads on blogs and Web sites. The service does two big things. One is letting you subscribe to any post's comments, regardless of whether the site in question offers notification of replies. The second element is scraping comments from threads you've replied to, so you can monitor and access the responses for multiple sites in one centralized location. If you're a frequent commenter on several different blogs or sites, this could be a worthwhile service for you.
In order to see if a page you're on has an active coComment discussion, you need to install a small Firefox extension. Alternately, there's a bookmarklet for other popular browsers such as IE and Opera. The key benefit in using the coComment extension is that it will automatically link your on-site comment with your watched comment threads. You need simply click the coComment button, and the service will give you the option keep track of the conversation, add tags, and mirror the thread to your watch list.
When browsing, the plug-in will change colors from blue to orange on any page you're on to let you know a coComment thread on the site or post already exists. Like the bookmarklet, when you click the plug-in button, you'll get the option to follow a thread or comment through coComment, instead of via the site's comment engine. This is one aspect that I don't like, since it's taking potential discussion off the site's built-in discussion. At the same time, for sites without the option to comment, coComment can add this functionality.
To keep track of what others are commenting on, registered members can become friends. Users can see who has subscribed to their conversation feeds, as well as see other coComment users who have responded to the same threads. Each user also gets their own comment and subscriber count, which acts as a general way to tell how much clout or interaction coComment users have.
Publishers can also integrate coComment into their blog or service. CoComment offers plug-ins for WordPress, Movable Type, and several other blogging platforms. Once installed, user comments can be hosted and by coComment, and made visible and searchable on coComment's network.
One thing I really like about this service is its exploration section. CoComment breaks down the most active users and posts, and does it in a way that lets you easily browse what people are talking about. From any coComment conversation, you can jump right to the original page, which turns the service into a social bookmarking tool.
Another thing I like about this service is that you install it and you're done. There's nothing more you need to do to use it--it will just begin tracking your commenting activity automatically. Many of the Web apps and tools I use the most are those that require the least amount of hassle, and coComment definitely falls into that category.