For the past few days, I’ve been trying out coComment, a free online service that tries to solve one of blogging’s thornier problems: tracking one user’s comments across multiple blogs.

While much of the fuss that’s being made over blogging in the traditional media focuses on individual bloggers themselves, blogs would actually be a lot less interesting if it wasn’t for the swarm of commenters that gather around them. The discussions they engage in can often be much more interesting and nuanced than the post that originally provoked them. And many folks are far more prolific at commenting on other people’s posts than they are at writing their own.

But tracking someone’s comments across discussions has so far been difficult, if not impossible. Ditto tagging those comments with keywords. And in a field that puts such a high premium on aggregating and remixing content, that’s a pretty big deficiency.

Enter services like coComment and (delivering even more power but also more complexity for commenters and bloggers alike) sxore. Using very different approaches, they allow commenters to register any or all of their comments – on (in theory) any blog out there – with a central server.

In practice, though, coComment has hiccups. For one thing, you have to remember to click on a bookmarklet in your browser toolbar to register your comment. More serious is the number of blogs coComment doesn’t work with: any blog powered by Drupal, for example. If the comments are delivered by a third party, such as Haloscan, coComment may have trouble coping.

And even on blogs it does work with (and in fairness, that’s a lot of them), it often has trouble pulling in the information it needs to track the comment properly. coComment wisely gives you the ability to fill that data in manually, and it’s hardly an onerous job, but it falls well short of the goal: an invisible stenographer at our side, collecting our every witty bon mot and “w00t!” for posterity.

It gets a little closer to that ideal, though, when you combine coComment with the Firefox web browser, the Greasemonkey extension for Firefox, and the Greasemonkey coComment automatic invocation script. Suddenly you don’t have to click that bookmarklet any more; coComment appears automatically on every comment screen. Now it’s just a matter of remembering to cancel it when you don’t want a particular comment tracked.

coComment has a few very cool features. You can display a box on your own blog showing the most recent comments you’ve made elsewhere. coComment provides an RSS feed, so you can remix your comments any way you want. And most recently, coComment has started allowing you to tag your comments with keywords.

This offers an interesting possibility. Using that RSS feed, it’s now possible – easy, even – to set up a blog that consists entirely of your comments on other blogs. Or a team blog that aggregates comments that you and your posse are making. Or one that only aggregates comments with a particular keyword.

There are more robust solutions out there. sxore is one of them, because tracking comments is just one aspect of how it tackles a broader question of online identity (in conjunction with its sibling technology, sxip). But coComment’s simplicity (when it works) is a big part of its charm, particularly in a field where simplicity is such a powerful factor in adoption.

And we’ve been blogging in an imperfect world for some time. Pingback, trackback and now comment tracking are all part of the (small-w) web of threads holding this big online conversation together.