The plot thickens!
I just registered for the site using Chrome on a Mac. I had no problem logging out of the site.. it logged me out and reloaded the page properly, and as expected. Can you let me know:
* What configuration you're using: Browser / OS?
* If it happens when you try to log out on any specific pages?
Also, try with a different FB user or other browsers yourself.. or clearing the cache of the browser you're using.. and see if that improves things.
Thanks,
Alex