Irrelevant, irritating, LOUD ads played in between movements of a single piece that are tied together. It's really irritating to be listening to something and have Spotify suddenly SCREAM at me the lyrics to some country song about taking my clothes off that I would NEVER be interested in, which Spotify would know if they could be bothered to look at my listening history, or even my last.fm account, both of which they can see. That said, I still use it to listen to music I haven't yet purchased.

My breaking point is that their library doesn't have the music I want to listen to. I own a lot of Rammstein albums, and if I can't have those on my mobile playlist, I'm not going to bother.

(Yes, I can have it pull music from iTunes, but then I'm having to manage two separate libraries, one of which could disappear overnight as a result of a court ruling. The odds of that happening are greater than all of my backups suddenly vanishing.)

Facebook.

Doesn't work in some countries.