Ah crap, I performed an apt-get -f upgrade and while it did allow me to update mupen64plus, it's installed Python updates that are screwing up other python apps.

Now both Gpodder and Panucci fail. They report:
ImportError: No module named cairo

Can anyone suggest an apt-get method to put my python version back to normal? There's so many python runtime packages, I'm not even sure which ones to look at.