Justin Timberlake joined Jimmy Fallon last night on The Tonight Show to conclude Fallon's first week of being the new host. While on the show, Justin performed his latest single from his album The 20/20 Experience 2 of 2, 'Not A Bad Thing'. In the interview portion, Justin and Jimmy did a hilarious reenactment of the Christmas SNL. In addition, Justin offered up a message to Buffalo because he had to reschedule his concert due to illness. Check it all out below.