One of the most shared videos this month is a YouTube performance by the band Karmin. The duo's cover of "Look At Me Now" by Chris Brown ft. Lil Wayne and Busta Rhymes has been viewed nearly seven million times since it was first trending on April 14th.

The video was tweeted by Questlove and Chamillionaire as well as Ellen DeGeneres, who later had them as guests on her show.

Karmin, made up of Amy Heidemann and Nick Noonan, has been posting videos since last fall. Until early this month, Karmin's most popular videos were covers of Bruno Mars and Lady Gaga, respectively. But none of those featured Amy's channeling of Busta Rhymes. It seems that hip-hop has been working well for the pair as their take on Lil Wayne's "6 Foot 7 Foot" has drawn half a million views in roughly 24 hours and is now also appearing on our Most Shared list alongside the original.

To what extent did that discovery boost their audience? The chart below shows viewership in the past few months:



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