I missed the end-end (I left when they started singing) so I dunno if that got better. I think if I'd known who any of the singers were (I didn't even recognize Sheryl Crow until Jack introduced her) it might have been funnier.
From what I remember, there was Michael McDonald, Cyndi, Sheryl Crow, Moby, two of the Beastie Boys, Mary J. Blige, Adam Levine from Maroon 5, Sara Barreiles, Clay Aiken, Elvis Costello... and other people that I can't remember.