I am using Ubuntu (Breezy) on my main desktop and laptop. Here are the steps I did to get them to act as a remote frontend. I'm sure within a couple weeks there will be new packages in the repositories, but for now:
Get these packages from:
http://deb.thehunter.ws/dists/breezy/mythtv-stable/
libmyth_0.19-3.i386.deb, mythtv-common_0.19.3_all.deb, mythtv-frontend_0.19-3_i386.deb, mythtv_0.19-3_all.deb

Uninstall any of the older above packages before you continue via apt-get remove.

Install the new ones as root:
dpkg -i libmyth_0.19-3.i386.deb
dpkg -i mythtv-common_0.19.3_all.deb
dpkg -i mythtv-frontend_0.19-3_i386.deb
dpkg -i --force-depends mythtv_0.19-3_all.deb

Grab the mythboxes /usr/share/mythtv/themes dir and put in /usr/share/mythtv on remote pc
Grab the mythboxes Free*.TTF (fonts) /usr/share/mythtv/Free* and put in /usr/share/mythtv on remote pc

On the knoppmythbox- comment out /etc/mysql/my.cnf line about skip-networking and restart mysql. (/etc/init.d/mysql restart)

On the remote remote-change /home/youruser/.mythtv/mysql.txt to IP of mythbox and change login/pwd to mythtv/mythtv

On the remote just run mythfrontend

If you have having the slowing problems with the program guide, search the forum for the fix or just create the folders and copy the icons to that new folders. (On mine I created /myth/channelicons and put them there)

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