When you mark up song information in the body of a web page, Google can identify it and, when users search for albums or songs, we may use this information to display links to those songs or samples in your search result snippet. Direct links to songs and videos in search results can help users better identify pages with good, relevant music content
The rich-snippets for music help creating the new albums with their details( eg. which songs, their duration and how we can find and buy them), which could be shown like the above picture on the google site. These details could be inserted through the form on the left side.