I know the rules of StackOverflow and hence apologize beforehand for asking such a subjective question.
I tried the documentation but all it says is this :
http://developer.android.com/about/versions/android-4.0.html
The new RemoteControlClient allows media players to enable playback controls from remote control clients such as the device lock screen. Media players can also expose information about the media currently playing for display on the remote control, such as track information and album art.
and a few more paragraphs on the subject.
It also points out:
For a sample implementation, see the Random Music Player, which provides compatibility logic such that it enables the remote control client on Android 4.0 devices while continuing to support devices back to Android 2.1.