I so unhappy that there is no option for disallowing the autocomplete from the taxonomy configuration page. I have a site that is part http and part https. I am using secure pages now and it is working fine. I tried taxonomy_autocomplete_settings but it did not work. It gave me AJAX error. This is probably due to the http/https. I tried to add the path to secure pages but it did not work either.
Users on my site create private organic groups. When a user enters a value in the free tag field that is attached to an OG content nodes (which should be private to the OG members), the user is able to see site-wide taxonomy vocabularies entered by others in their private OG. Of course this is not acceptable and needs to change ASAP. Does anybody have idea what to do or how to get rid of the autocomplete function on certain content types, especially those OG content?