Paul has been adding things to his RSS feed. More specifically, he now has the <comments> attribute. I’ve followed suit (in the RSS 2 feeds) as of just now. The only reason I hadn’t done it before was that I was under the impression that the comment attribute was the url at which you were to add and view comments. Since Epistula (And Klind before it) doesn’t work that way, I ignored it.
We also have the slash:comments stuff, which it would be nice if somebody used, and the dc:subject for categories.
And people wonder why I think RSS is overly bloated?