I didn't see anyone else posting anything about the Playstation Music app, but I had a couple suggestions for the app while I was looking at it earlier. Playstation has said that they want to be "more ubiquitous" and essentially be the center of the living room, and Spotify has made notable contributions to that with a lot of features they've rolled out like the ability to switch between devices with ease. Spotify knows that social is the future, and being connected is a key point to being a successful business in today's society. That being said, I felt that the collaboration with Playstation on Playstation Music, while very cool and very well designed, is way too limited.
FEATURES TO ADD:
That's all I can think of for now. The lack of a social feature was the thing that most bugged me. You guys have a pretty good design team it seems like, so you probably already know what it needs. But I thought I would put in my two cents.