You learn something new everyday! Here were I answer my own question...
I had a poke around the httpd.conf file and found this setting for rendezvous:
<IfModule mod_rendezvous_apple.c>
# Only the pages of users who have edited their
# default home pages will be advertised on Rendezvous.
RegisterUserSite customized-users
#RegisterUserSite all-users
# Rendezvous advertising for the primary site is off by default.
#RegisterDefaultSite
</IfModule>
I didn't know that the default page had to be changed. So I went in and added a couple of word to Panthers default index.html page and I can now see my site!
I could have also commented
RegisterUserSite customized-users
and uncommented
#RegisterUserSite all-users
That will allow all the sites to be seen!
Was this behaviour in Jaguar?