Just pushed a fix that should make RSS feeds work properly (you will have to resubscribe to the RSS feeds, if you did so a while ago). Thanks to squirrelInHell who made me aware of the deeper problems with our RSS feed (that my RSS reader seemed to mostly automatically patch, but which other people ran into).
greaterwrong has them:
Feeds for just the comments, just the posts, or both comments and posts, of an individual user (for example, here’s Eliezer Yudkowsky’s comments feed); these are accessible from the user’s page (e.g., here’s Eliezer Yudkowsky’s page)