Attention Demonbeck and others, I’ve made some adjustments to the site.
First, the “Recent Comments” block should be fixed.
Second, when you go into posts now you’ll see a little square to the left of each comment. A gray square means the comment existed when last you went into that post and a gold square means the comment was added since the last time you went into a post. The visualization should make it easier for you to get to the comments you have not read.
Please note that if you mark all comments as read in the “Recent Comments” block at right, it will not affect the gray vs. gold blocks. The gold blocks will not turn gray until you have actually clicked on a post.