For all those having issues with Spotify on Beta 3, you need to delete and re-download the app from the App Store. It will download an older version (0.6.4.2) and then offer an update to 0.7.1. If you don't update, it will work fine. It's odd behaviour, but it fixes the issue. The older version has the old Spotify log (all green), whereas the newest release has a black background with the green Spotify logo in the middle.