I just installed the commenting system Disqus to manage comments on this blog.
Disqus is a hosted service that replace and enhance the native comment system of your blog — Disqus support the most popular blogging engines but can work on any website — by adding threaded comments, video comments, email & mobile replies, tracking & subscription, ratings, spam protection and more.
Disqus have great features and is a real improvement over the WordPress native commenting system. However having to host the comments on a 3rd party service was my main gripe about it.
What would happen if I don’t want to use it anymore, or switch to a different service?
With Disqus 2.0, this limitation is now gone. All comments are synced back to your WordPress database. Neat.
Disqus also includes a built-in social network with profiles. Tracking conversation over multiple blog can be a pain, but with more and more people joining the Disqus network, I can track them right from the Disqus dashboard. Here is my profile on Disqus.
If you commented on any blog powered by Disqus without having an account, no need to worry, you can claim your profile and get back the ownership of all comments you posted so far.
Installation of the WordPress plugin is easy. When configured, you can import all your WordPress comments to Disqus. CSS-ing is another good point. It’s straightforward to customize the comment widget to match your blog style.
The Disqus team is very active and respond quickly to user problems. I had an issue installing the plugin with an older version of WordPress (2.3); posted a message on Twitter about that; Daniel Ha (co-founder of Disqus) replied to me immediately and helped me figure out what was wrong. Thanks!
However, Disqus still need improvements: (1) I can’t edit comments — I generally rewrite comments for typos; (2) I still have an issue with trackbacks, I don’t know if they have been successfully imported but they don’t show up; (3) email subscription.
I’m pretty sure these issues will be fixed soon.
UPDATE: edit is now enabled for your own comments.
CTO at 
Comments
Fred,
Couple things:
1) Editing will be making its way back in soon. You won’t have to do anything on your end.
2) Trackbacks will not be imported at this time as Disqus has its own trackback system. I think allowing WP trackbacks is a good idea and we’ll investigate this.
Daniel Ha19 August 08 at 1:08 pm
Thanks for the info. However, I’ve seen on other blogs that the “trackback URL” should show up at the end of the Disqus thread, but it’s not on this blog. I only have the “trackback” title.
Fred Brunel19 August 08 at 1:20 pm
It's been working pretty well so far. I'm waiting to see how the integration of IntenseDebate with WordPress can change that.
Fred Brunel15 October 08 at 11:41 am
It doesn't seem to work actually. It's supposed to.
Fred Brunel16 October 08 at 6:08 pm
Video commenting is pretty cool indeed, even though I think leaving a video comment takes a lot more effort than just writing.
Fred Brunel30 March 09 at 1:15 pm
DISQUS synchronizes comments with WordPress so there are still in your database.
Fred Brunel8 July 09 at 4:27 pm
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