Some analysts are skeptical that Twitter’s new service represents a major step forward for the music industry. Twitter Inc. says its new music service helps users discover songs and artists. But the music industry isn’t sure it’s something to sing about just yet. The #Music app recommends songs based on the artists Twitter users follow. It also shows what tracks friends are tweeting about. And it lets users browse songs that are popular or up-and-coming on the service. The user can preview the tracks from iTunes or subscribe to Spotify or Rdio to listen to full-length versions of the suggested songs.