I don't use minidisc's myself - I'm a floppy disc shuffler on a PSR2000 - but I've worked with a number of cabaret artists who have their (orchestral / midifile) backing tracks on Minidisc. They use it as nothing more or less than a replacement for cassettes, with the advantage of better sound quality, random access and named tracks. I appreciate that the sound quality can only be considered equivalent to mp3, and under studio conditions you can discern differences, but in the places I play such differences are indiscernable, and nothing compared to the sometimes shocking variation in quality of the backing tracks used.

I would agree that minidisc's time has probably gone; it never really caught on the way Sony would have liked and the cheapness of CD burners and the availability of very portable and lightweight mp3 players means that for a lot of users there are now better / cheaper / smaller options available.