The world leader in identifying and ranking hit songs has long been Billboard. This week they are updating their "Hot 100" formula to include youtube video hits for a song like Bauer's "Harlem Shake" that has inspired lots of user uploaded videos of ridiculous party behavior and really bad dancing. That song will debut at #1 this week, which is reasonable considering that there's no doubting it's the #1 hit song right now. Amazing that the song was released in May 2012 and debuted #1 in the charts in February of 2013.
From Billboard's Biz site:
Billboard is now incorporating all official videos on YouTube captured by Nielsen’s streaming measurement, including Vevo on YouTube, and user-generated clips that utilize authorized audio into the Hot 100 and the Hot 100 formula-based genre charts -- Hot Country Songs, Hot R&B/Hip-Hop Songs, R&B Songs, Rap Songs, Hot Latin Songs, Hot Rock Songs and Dance/Electronic Songs -- to further reflect the divergent platforms for music consumption in today’s world...
The inclusion of YouTube streaming data comes nearly one year after Billboard and Nielsen launched the On-Demand Songs chart and added streaming data from leading on-demand subscription services such as Spotify, Muve Music, Rhapsody, Slacker, Rdio and Xbox Music to its chart and tracking offerings.