Same issue for me on IE8 running W7 on my work computer. No ability to upgrade to a different browser. That really sucks. Once I'm in a thread it looks fine, but it is a huge pain in the butt to try to see what threads are there. Makes the site essentially unusable for me during the day.
What is really strange is that it worked just fine on the beta site and I believe a little after the actual go-live, but I'm not positive about that. However I'm 100% sure that it worked just fine with beta.
That tells me that there is something that had to have changed.