1. Default iTunes Radio view from the lock screen... just shows album art.
2. As in iOS 6, if you double tap the home button it brings up the music control options.
I'm not sure if it was like this before, but now I noticed the options are still visible even if you lock the screen and then unlock it again. They only go away after double tapping the home button again.
3. You can access the Radio features right from the lock screen by clicking the star.
If it's just a regular song playing from your library the only difference is that the star is replaced with a back arrow to restart/play the last song.
4. What the iTunes Radio advertisements look like