If a user with write permissions for a page changes the Options fields on the Page Properties popup, changes to the Page Title and Template fields are correctly controlled by workflow -- they appear only on Edit and Preview until published Live and only a user with admin rights for the page (or site) can do this. However, changes to Page URL Key immediately come into effect on Live -- viewing the page in Live by the previous URL shows no content, clicking site links to the page go to the new URL with the current Live content shown.

Changes to the Page URL Key should be controlled by workflow and remain on Preview/Edit only until a user with the appropriate rights publishes the page Live.

If this change is not possible, there should be an option under Manage Site Permissions to restrict users from accessing this setting. My client requires that users without administration rights not be able to make any changes direct to Live without moderation.