Before I submit this as a ticket at WordPress.org (in case my problem is due to some plugin, for example), I wonder if anyone here could confirm the problem I'm seeing after upgrading to 3.5.
Namely, the actual post titles do not show up for Private or Protected posts. The phrases "Private:" and "Protected:" do appear, but not the actual titles. I'm using a child theme of the most current "twentyeleven" theme, but the problem also appears in the Live Preview of twentyeleven and twentytwelve - without my child theme.
If someone's got 3.5 installed, I wonder if you wouldn't mind publishing a simple private and/or protected post and reporting back (please include theme).