Same Feature like MixedInKey: Show mean loudness of a track in Playlist

An advanced but very important feature is offerend by software mixed in key, as they analyze the mean loudness of a track. That is incredibly helpful creating playlist in respect to start silent and get louder. The scale could be maybe shown on a scale between 1-10 or any other metric. So you will have another id3 tag or could put that info to the comments.