Number of comments not updating on posts since WP Upgrade

I recently (finally!) upgraded to WordPress 2.x and I’ve noticed that on any posts published since the upgrade, the number of comments is not updating on my main page or on the single post page.

I use Brian’s Threaded Comments plugin, which I’ve got working fine (I think), but I’m not sure where to start in figuring out what the problem might be because it doesn’t make sense to me that the posts published under 1.5 work fine, while the posts under 2.0 do not.

Anyone have any idea what the issue might be or where I might start looking to find a way to fix it?

http://www.withinwithout.org

Thanks for any advice you can offer.