There are many cool easter eggs in iOS 7 such as the funtional clock app icon, the functioning weather icon, so on and so forth.
What you didn't know about iOS 7 is that the Music app, now automatically downloads the art corresponding to the artist. For example, if I were looking for Bob Dylan in artist view, it would automatically download the artist art. This is only found in iOS 7 beta 2. It does this all automatically without user administration, which is impressive.
Apple has done a nice overall job of improving the Music app from one beta to the next, and I am impressed.