Given how dominant YouTube is as a place for young people to listen to music, its notable how slow Google has been to embrace radio partnerships. The YouTube 15, which will be hosted by YouTube personality Jenna Marbles, will air on Fridays starting July 11th at 6 PM ET, and replay throughout the weekend. YouTube is lending Sirius XM its name and data around video views to help Sirius programming executives choose which songs to play. The show will highlight artists who are emerging on YouTube as well as other pop songs popular on the platform, the companies said in a statement.