Lost ability to select from content taxonomy field

I have lost my ability to select a term from the content taxonomy field.

The attached image (userview.gif) shows the endusers view of the page. Note the items highlighted in yellow are from a content taxonomy field.

Screenshot node-edit.gif shows the edit view. Note the ability to select a subject or resource type (content taxonomy fields) is gone! I've tried checkboxes, multiselect, select list, etc. and nothing works.

I've tried deleting all caches. Reinstalling from a backup. Reinstalling the taxonomy modules, and still can't get it to work.

I have the pages working on another system running mysql 5.0.27. The only change to the system was upgrading to mysql 5.5.14. Could this be what broke it?

Arg. I've spent all day trying to get the fields working. Ideas? Thanks!