I also had the time (and the idea, thanks Olimar) to check Totem for RTL issue. Surprisingly, didn't have to change much, GTK+ did quite a lot by itself. In the end, it was a matter of moving the fullscreen popups to the right hand-side, and swap the icons for previous and next.
Watched Good bye, Lenin!. Some damn good film that one. The German Amelie, or something.
Update: The nice RTL screenie.