I took the plunge with a apt-get dist-upgrade today.
Fortunately I did a complete system-backup with partimage.
I got the new mythtv .22 installed and had to drop the mythconverg database.
After recompiling v4l I also got my tv-card running again, did the station scanning and everything else to get mythtv running.
So far it seemed nice, even on my MD, but its only running for a few seconds. Mostly I get something like this
video frame buffering failed too many times
at other times it seems, like the frontend cannot find the backend-server and asks if the IP has been setup correctly.
does anyone else has some experience with the new mythtv?