Twitters social music discovery service might have failed, but that hasnt stopped the company from partnering with Billboard to launch the Billboard Twitter Real-Time Charts. The website measures the popularity of songs in the US by scanning Twitter interactions for links to music listening platforms like Spotify or iTunes, hashtags such as #nowplaying, and the presence of words like track and listen. The first is Billboard Trending 140, which compares the frequency a song is shared over the past hour with the hourly average of shares in the last day. The second is Billboard Twitter Emerging Artists, which ranks songs from artists with less than 50,000 Twitter followers by the volume of shares in a 24-hour period.