Beware. This may or may not be related, but for everyone's knowledge:
I was also impacted by the Match issue for the past couple of weeks. I was finally able to match songs earlier this week, and moved on with my day. I create backups of my iTunes music directory on a monthly basis, and ran it for the first time in July or August today. My backup software warned that there were random album songs present in my backup that were no longer present in my source directory.
It was all random. Random artists, random albums. There were about 20 albums missing a single track, and in a couple, missing two tracks. Random track numbers. I copied each from my backups over to the iTunes directory and didn't let my backup/sync software remove the source files.
Had I not noticed, that would have been a huge pain to detect and fix later.
That has never happened before, and I do not delete random album tracks from my iTunes library. It seems like an odd coincidence for that to happen right after iTunes and Match had an extended problem. Who knows, maybe not related. Odd though.