Matt & Kim "Block After Block" (live on 'Fallon')

Matt & Kim "Block After Block" (live on 'Fallon')
Endlessly grinning duo Matt & Kim took their ridiculously sugary brand of pop to Late Night With Jimmy Fallon, where they offered up a performance of "Block After Block."

Check out the high-energy clip below, and watch to the end catch a glimpse of the Roots imitating the band's stage moves.

Thanks to The Audio Perv for the video.