Elvis Costello and the Roots' Wise Up Ghost is looser than you expected, less stuffy than you feared, per our review, and you can see for yourself in their late-night TV performance of gruff R&B opener "Walk Us Uptown" above. The September 17 clip also brings to mind another brassy, groove-oriented combination of an elder statesman and younger talent, David Byrne and St. Vincent's Love This Giant, which, hey, hit the Late Night With Jimmy Fallon stage almost exactly a year ago. Costello, a Fallon regular at this point, also sat down for an interview, complete with man-of-mystery jokes that set his host giggling giddily. Also potentially of interest: Justin Timberlake joined Jimmy for a skit that involves the two singing Hootie and the Blowfish. They only wanna be with you.