A cool features can be to send approval confirmation message to user have post entry in guestbook... In fact when new entry are made (and if we have set to Admin approve message before publishing) Admin receive email notification for say that...but when Admin approve that message user don't know if his message are approved or not...The only solution for user is to come back for see...reason why a simple approval confirmation message (and configurable in any language) can be very nice...It increase website traffic and show to user we are serious with his comment...
Plan you to make it in near futur ??
Anyway your Guestbook are pretty cool like that and it is free...For sure is not necessary to always add thousand of option...simple things are always appreciate to anybody....but if you have little time...
