If you haven't heard of Medibuntu, it's probably because you are not using Ubuntu.
Medibuntu provides a package repository for some multimedia applications that can't be integrated in the official repositories due to legal problems in some countries (libdvdcss is a well known example of such software).
The project is currently maintained by Lionel Le Folgoc (aka mr_pouit), and it's not an easy job! I've tried to help the dev team now and then with a few contributions, but it wasn't quite enough. I intend to be more active from now on.
On the packaging side, I've started with ffmpeg-extra and mplayer updates for maverick (to add faac support). A bunch of packages have been removed for this release (google-earth, realplayer and gizmo, for which upstream provides deb packages or easy installation tools). The other packages seem to be in good shape and ready to be used.
I'll also handle the main server and the mirroring frontend (thanks to all the kind people who host mirrors!). Some of the mirrors have been updated, some are still behind. If you're lucky you might be able to use the maverick repo... I hope to have everything ready for the Ubuntu maverick release, but I can't guaranty that.
Some more formal announcements will probably follow in the next days.