RSS feeds for user's comments seem to be broken with the update to how they display on the page. To see how, just look at eg. http://lesswrong.com/user/Yvain/overview/.rss . It contains a bunch of comments from other people than Yvain. This is pretty annoying, hope it's fixed soon. I'm subscribed to tens of users' comment feeds and it's the main way I read LW. Today all of those feeds got a bunch of spurious updates from the new other-people-comments on everyone's comments page.

Also, some months back there was another change to userpages and it broke all my RSS feeds too, I had to resubscribe to everyone's /user/theirname/comments page where I had previously subscribed to the user/theirname page. I wish updates would never break RSS feeds, I'm sure I'm not the only one who makes significant use of them.