a new feature of GAL in zimbra 7 is
"Global People Search
Need to find a phone number or email of a peer not in your personal Address Book? People Search is a convenient Global Address List search tool available from anywhere in the Zimbra Web Collaboration experience.
* Search autocompletes results as you type
* Displays photo, phone number, email, title and location
* Works with both Global Address Lists and personal Address Book contacts"
tried to update the photo/image from the admin web interface or zmprov... no success
-it's displayed when hovering over a gal contact
-cannot be changed from the admin web interface
-can be changed only with zmprov