Oops! Apparently the Guestmap feature isn't foolproof. I visited the map today to see what new entries were there, and most of the ones I had were just gone. So I visited the Guestmap help page, where I saw this:


Troubles

All at once some dots and messages on my GuestMap are gone! What happened?

Once or twice a day we delete all no-comments-messages from all GuestMaps. Why? Because it enhances the quality of your entries and our datafile. Furthermore the GuestMap displays only the latest 40 messages. Older messages will "fade out" automatically.


As far as I knew, there were no messages "without comment", and I hadn't hit 40 messages yet. But the help page also states that this is beta software that isn't guaranteed to work. C'est la vie.