http://news.yahoo.com/blogs/the-difference/buzzy-moments-decade-difference-concert-041922282.html
http://tinyurl.com/3hkqon6 Singing begins around 1:20, including a bit of Italian opera. ;-) (This page also has videos of Stevie Wonder's and Usher's performances. Usher does a Cockeresque version of "With a Little Help from My Friends." The whole concert is available on video here.)
