Today we’re releasing a new feature that helps you better understand the viewing trends of your YouTube videos: a discovery tab that shows how viewers found your video, whether by searching on YouTube or Google, browsing under “related videos,” receiving a link to the video from an email or website, or watching it in an embedded player off YouTube.
— YouTube - Broadcast Yourself. : : understanding how people find you is one of the keys to making better decisions about how you are marketing your videos. Good move, YouTube. 4 months ago