For me, control highlighting in 16.10 is an absolute show-stopper so I really want to emphasize the issue and refer to this demonstration in the future.
Here is the shutdown screen when tabbing between buttons on Mate 1.14.1 vs. 1.16.0 (Ubuntu-Mate 16.04 vs. 16.10):
Believe it or not, they are tabbing between the same buttons at the same time. If you look closely, you can see how 1.16.0 has a very subtle darkening of the font but otherwise near-useless highlighting. My normal screen resolution puts it around the limit of perception.
I'm always keen to a workaround. Anyone have any pointers how to edit such settings in /usr/share/themes? It may be an easy fix.