I had a chat with Emiku about this. The changes niz23 did to the media_plugin only affect the people who recently installed a snapshot.
To verify that this indeed is the problem, could you install the version I have:
apt-get install --reinstall pluto-std-plugins=220.127.116.11.10072723202
Yep, that's it. Installed your version and everything works.
Thanks posde and Emiku. I'll avoid doing apt-get upgrade for a while.
FYI: I installed the snapshot from 2nd August (23227).