Just a short update. After using the MyMovies Collection Manager for some time, I've given up on the idea of early-testing the MyMovies port for SageTV. The collection manager is just a total piece of shit and every second spent using it is a load of frustration.
It's a rip-off of the DVDProfiler UI, which is not at all suited to managing files. There are about a dozen other programs with better interfaces that could have been ripped off to make this at least half-usable. This program is written by the official MyMovies people from Denmark - and the whole MyMovies plugin for MCE is commercial. There are restrictions to the amount of data you can poll using the client unless you're a full customer of their product or have contributed a certain point value of data submissions yourself.
The MyMovies port for Sage is the effort of a Sage user and has to be commended. However, after reading the instructions to get the plugin installed into SageTV, I've decided to skip it until at least a one-click solution is available. There were just too many hoops to jump through.
At this point I believe I have pretty much decided with 99% certainty that I will be buying a Boxee Box when it's available. The latest beta addresses a few UI glitches I previously mentioned, though it still doesn't properly sort titles beginning with "the."
If I wanted to build/design my own solution to this problem, I'd do that. I want something polished and finished and just ready to go. I don't have much hope this level of finish will be present in SageTV itself, so I'm left with having to choose a second box for file playback.