The crux of the problem is not necessarily that syndicating comments is hard to do. It’s not. Even before WP stored comments in blog-specific DB tables, there was always enough information about the comment-post relationship to provide the infrastructure for creating comment feeds, etc. The problem is that comments are not unidirectional. When I write a blog post, WP acts as a hub that sends the immutable text out to my hundreds of thousands of millions of avid readers. Comments have to work in the other direction, with users sending information my way. Right now the only real way for that to happen is for them to actually direct a browser to my blog. There’s the problem: you can write a blog post via XML-RPC, via e-mail, or via some other API, but not comments – that’s platform-lockin, or UI-lockin, which is the opposite of platform-agnostic standards.

So comment writing is one part of the problem: coming up with a way that people can comment without visiting my blog. By extension, and more closely related to the FWP point, people should be able to comment on my blog by commenting on another (aggregator) blog. The Disqus solution I hacked together here does a good job of that, and I could easily write a plugin that would allow you to do that on a single installation of WPMU (btw, oh shit, I meant to do that last week), but you can’t do it in a truly distributed way.

The other conceptual distinction between comments and blog posts is that, to a certain extent, blog posts provide their own context. Thus when a post from the bava comes through my feed reader, I don’t necessarily need to leave the reader to know what’s going on. Comments are almost always very post-dependent for their content and context, so they don’t make much sense by themselves. This calls for some sort of new innovation in reader design – in other words, I think it’s a UI problem, not a standards problem – that pulls comments from places I’m interested in and allows me to read them in context without having to visit 25 different blog sites throughout the day. Pages like iGoogle are the start of a way to think about what such a UI might be (totally personalizable portals that bring together content in a context that you get to determine, rather than the linearity of the feed reader) but a lot more work remains to be done, by people smarter than I am :)

The only issue I have with Disqus and intense debate, etc, is that the are services, not standards, for getting these comments syndicated back and forth and giving people some control over those comments. And now that wp.com immediately gives you an ID account and immediately locks you in suggests a kind of battle for this space that wouldn’t integrate with Disqus that cleanly, but I may be wrong. Since about 2.7 on WP/WPMu the comments were associated directly with posts, which is new, and I don’t know enough code, and this wouldn’t solve larger cross-platforms issues, but it would possibly allow direct syndication on a post-by-post basis. But how TypePad, Blogger, and the like do that is a larger issue. Stephen Downes suggested that the way to solve this is to link commenting with a personal identity online through something like OpenID and the like, which is what ID and Disqus are approaching. But the thing about these two services is they are services not something you host and own yourself.

It remains an ongoing question, but given the roll you are on, it may be worth a shot :)