Bug #652238 calls for the removal of Orca's gnome-mag support from Orca's master branch. (As a reminder, people who really want to use gnome-mag can continue to do so via Orca's gnome-3-0 and orca-xdesktop branches.) Once this removal is complete....

The Magnification page in Orca's Preferences dialog was intended for gnome-mag configuration and includes a number of options that are not available for gnome-shell mag. In addition, Joseph is working on a gnome-shell mag configuration gui which will be incorporated in the control center (or someplace other than Orca, anyway). Therefore, for now, we'll remove Orca's Magnification page. And then we will monitor the situation with Joseph's work. Worst case scenario is we incorporate his GUI into Orca's. But I see no good reason to do so unless and until it becomes essential for us to do so (i.e. because it is not included anywhere else).