Besides the obvious bands and music producers, this could be a great promotional tool for marketers.

With a single tap, the Twitter Audio Card lets you discover and listen to audio directly in your timeline on both iOS and Android devices. Throughout your listening experience, you can dock the Audio Card and keep listening as you continue to browse inside the Twitter app. We’re launching this new audio card in partnership with third-party streaming services. The first partner for streaming on Twitter is SoundCloud.Twitter Ads Audio Card Allowing Music and Audio Listening In The Timeline [blog.twitter.com]