OK, so in a fit of ill-advised non-thought, I updated my music software on my computer and, in the process, wiped out my playlists, along with some random pieces of track data here and there. Mostly there. Anyway, what is most frustrating about this is that at one point in the past I had managed to back up the playlist data, which means that at that point in time I actually knew where on my computer it was stored. Couldn't find it yesterday, of course.
I realize that this same thing has happened to other people, because I remember reading about it and thinking Oh. Poor. Man. So now we can add to that, Oh. Poor. Goddess.