Keith Urban & John Mayer ‘Don’t Let Me Down’ at Crossroads Guitar Festival at Madison Square Garden [VIDEO]

Keith Urban has been a busy guy lately.  He was in Vegas last weekend for the ACM Awards.  Then he flew to L.A. for American Idol on Wednesday and Thursday.  Then it was off the New York City on the red eye for the 4th annual Crossroads Guitar Festival at Madison Square Garden. He teamed up with John Mayer to play 'Don't Let Me Down' from 'Let It Be.' 

AND he had to time to send me a personalized birthday card.  When does this guy sleep?