Just thought I'd add my experience:
I've got LinuxMCE 0810 (Hybrid + 5 MD's) running along-side a few working machines which must remain stable and connected. These working machines have all been upgraded to Kubuntu Karmic, and thus, MythTV's database versions were off, and wouldn't play nice with the LinuxMCE Net. As well, on our Android-Powered G1's, we've attempted to use nearly everything available for remote control of MythTV, and I seem to remember that we needed some new tweak on the frontends, for use of Mythmote. There may have been other reasons as well, but these were the main ones that I remember...
I did some googling, and found that the Avenard repos that we're using, "release testing" were just a tad behind the DB version used by default in Karmic (or vice-versa), so changed it to "release testing trunk", and now all are in sync.
THE POINT: The Avenard Repo's trunk versions of 0.23 are PLAYING NICE with LinuxMCE, and have given me no more trouble (with my cheap-a$$ capture cards and such...) than LinuxMCE normally has. Might be worth looking into?
Loving the way 0810's been running, the last few weeks!! Mega Thanx to all the folks making it happen!!