Sony has announced that Spotify will launch today on PlayStation 4 and PlayStation 3. You don't need PlayStation Plus to use it, and it sounds like you don't need a Spotify premium membership.
Spotify's paid program removes the ads, improves audio quality, and gives users access to music offline on mobile devices. If you want to try premium ($ 9.99 per month), there are a couple of ways to get a free trial. If you had a Music Unlimited account active as of March 29, you get two free months of Spotify premium. If you've never used a trial of the service, you can get one month for free.
Using the iOS or Android app, Spotify users can control their music on the console. This allows you to add custom soundtracks without pausing.
The service is available in 41 markets and Sony is calling the partnership "exclusive."
[Source: PlayStation Blog]
It's a shame we're paying for custom soundtracks, a feature that was available on last-generation consoles by default. I can't imagine using the free version in that capacity, as the last thing I want to hear when playing Bloodborne is a Geico ad. If you're already a premium member, this seems like a good extension of your existing membership, though.