Karen O’s “The Moon Song” returns — Oscar nod in tow — for a duet revision co-starring Vampire Weekend’s Ezra Koenig. This take fits the Spike Jonze film well: It’s also a duet in Her, where Joaquin Phoenix (as Theodore) and his dream-droid, Scarlett Johansson (as Samantha), harmonize on a binary lullaby. Koenig’s vocal echoes that narrative a bit here, too, recorded remotely after the fact, yet still in sync with the tune’s tender core. Update: Watch a live performance featuring O, Spike Jonze, and KK Barrett: