Logout to see what they can see - headings and no messages as far as I can tell!
There is little point on being on the site without registering.
If you look down the bottom of the home page you can see the "users on line". When you go into this area you can see what topics everyone including the users are viewing and its not just the home page. Also if you google Aussie pinball you can go into "Recent Posts" with out logging in and read all of the latests posts on there.