Thanks for mentioning that. I ended up using schedulesdirect and everything on the backend (on my hybrid/core) works great. But because Canada isn't supported in the LinuxMCE setup, I had to configure MythTV manually rather than letting LinuxMCE auto configure everything for me.
Later, when I created my MDs, MythTV wouldn't auto launch on the MDs and exited after about a minute. From the responses I've received, it appears that if you cannot complete the LinuxMCE MythTV setup (and end up choosing Don't Auto Configure option) the mythfrontend settings needed for LinuxMCE to control MythTV on the MDs are never configured. LinuxMCE then kills the mythfrontend after about a minute because it cannot be controlled. Configuring the "Network Control Port" option manually on the MD solves this issue for me.
I'll look into what it would take to get the initial setup working for Canada using SchedulesDirect. But it would be nice if there was also an option in LinuxMCE to auto configure everything in MythTV except for the guide data or tuner inputs.
I'm hesitant to just disable the "Don't Auto Configure" option because of the troubles another user had: http://forum.linuxmce.org/index.php?topic=10699.msg73671#msg73671