Not too sure what does that. That happened to me as well for about 4 months or so...really stunk whenI couldnt remember what thread I wrote in or was watching...etc. However, now its back to normal. Id say zip off an email to Lamont and ask him.
Until you get that fixed, here is another route you can take:
1. make sure you are logged in.
2. Click on the Forum Index (NOT the general board or any other board...just the index itself).
3. on the top of that grey box on the right, you should see "view posts since last visit, ' ' view your posts'..etc. The 'view your post' should work for you.