There was some pretty big news yesterday regarding the US release of Spotify. Namely, that it's actually going to happen. Can anyone familiar with the service tell me what sets it apart from Rdio? I'm sure there are some UI/UX differences but isn't it the same thing? I think I still need some convincing on the whole No Local Copy of Your Music Archive mentality - especially given that 3G service doesn't exactly blow my mind, so mobile streaming still seems a bit far off.