Last week YouTube announced the launch of Music Key, a new premium subscription service that will let subscribers stream high-quality, ad-free music, videos, covers, playlists, remixes and more. Music Key will differentiate itself from services like Spotify and Pandora with unique features.For $9.99 a month, subscribers can listen to music with or without video, receive access to millions of official videos, album tracks, concert clips, etc., and listen to music offline or while using other apps. Music Key also includes a subscription to Google Play Music with more than 30 million songs, playlists and official music videos, giving subscribers a two-for-one deal.Users who are selected to try out Music Key during beta testing will get six months free, and will pay a discounted rate of $8 a month to keep the service thereafter. To appease everyone else, YouTube has added free music features to its online and smartphone platforms. These new features include ads, but are designed to hook consumers so they will become buyers when Music Key becomes available, a strategy that has worked well for other streaming music services.Though an ad-free subscription music service isn’t news, the fact that it is coming from YouTube and will include videos is. With more than a billion unique video visitors per month, according to a CNET article, YouTube has a greater reach than any other music source online, and it is the top site for people age 34 and under to find new music. A Nielsen study confirms YouTube’s reach, citing that more than two-thirds of Americans listen to music online each week, and their number one source of music is YouTube.Though its monumental size and reach alone are not enough to make Music Key successful, access to millions of potential subscribers is certainly a good start. By leveraging its video advantage, YouTube has the opportunity to create a truly unique product and steamroll its competitors by giving music fans features they can’t get anywhere else.