I've been signed up for about a year and a half, and I'm generally impressed. My usage comes in cycles, and currently it's been a month or more since I've listened. On the upside of the cycle it's pretty much a continuous thing. The main reason I stop listening is when I'm programming multimedia stuff and need to avoid conflicts with audio devices.

Their training algorithm seems pretty effective, if you're willing to spend a few months giving it input. At first I was constantly clicking the thumbs-up icon, but after a while I'd go to do that and find that the song was already on my favorites list. Now I rarely bother. I find myself wishing for a middle choice between thumbs-up and -down, "don't care so much any more" to apply to songs originally marked as favorites, because early on I stuffed the ballot box to force the system where I wanted it to go. Songs I used once to bracket a genre aren't really my favorites, I was just trying to make a point, and I'd like to downgrade them without actually rejecting them.

The algorithm has some awkward corners that may be ineradicable due to licensing strictures. You can try to train it by example, by naming a song you like; but because their license agreement prohibits playing requests, you guarantee that you will not hear that specific song for a while, only songs that the system judges resemble it. They seem to try to exploit some kind of version loophole, though; you may not hear the exact performance you flagged, but you might hear the "unplugged" or concert version. And, finally, for the same reason, you hear a lot of obscure "B" tracks, which is sometimes a treat, but more often you're just reminded why a song sank without a trace.

Oooh, oooh, it's playing "Freebird"! I'd requested it months ago, but as noted, I had to wait for my "request" to expire.

That reminds me of another flaw: No rewind or positioning slider, I assume again because the "studios" don't want people to control what they hear and potentially record it. Too bad. I could've listened to "Freebird" a couple more times.

And after "Freebird", now it's playing "Ohio" by Crosby Stills Nash & Young. Sweet. You can share playlists, so here's mine.