“Because the Internet has changed how people discover and share music, the rules of marketing it and the hierarchy of who determines what’s hot have also changed. As radio-music listenership declines, the industry finds itself spending more time courting a broader field of tastemakers who, through Web sites, are popularizing songs that never get radio play. The primary tool in this transition is the playlist — a sequence of tracks posted on blogs or shared on music purchase sites such as iTunes.”

Read the full article on WashingtonPost.com.