The labels still don't get it. This LA Times New Times (thanks, boogah!) story is an excellent overview of the problems with the labels' music download services — limited selections, horrendous abridgements of fair use, and high cost of use.
But even for those who aren't particularly attached to plastic discs (or liner notes, or cover art, or lyric sheets), the impermanence is still problematic. MusicNet's the worse of the pair, with a cap on songs downloaded per month that's absurdly skimpy, especially when you realize that retaining some songs for the next month re-deducts them from that month's quota. In other words, if you downloaded "…Baby One More Time" in January and you want to hang on to it for February, you're going to have to give up a download one more time, baby. And with a 100-song limit, the most you can accumulate at any given time through MusicNet is about 10 albums' worth. Try impressing your friends with that collection.
(Thanks, Boogah!)