When and if the metadata-extractor library can support it reliably, jAlbum should populate the gpsLocation variable with the GPS coordinates present in an MP4.
In the same vein, the Location panel in edit mode should allow the user to provide missing GPS coordinates, or alter existing coordinates.
(This has come up a few times in other contexts, or in threads that got hijacked onto tangents. This is an attempt to memorialize it in one place, in a clean form. Posts that derail the discussion again will be deleted.)