Glee - Yeah - Usher Cover

An all-female a cappella group sings 'Yeah' by Usher on the Glee finale. The group is unknown for now (they're not the New Directions girls), but I wonder if the voices are from a previous season of The Sing-Off (just like the Beelzebubs aka Warblers).

They also changed the lyrics.

Listen:

http://media.mtvnservices.com/mgid:uma:video:mtv.com:654781