Karen O at Firefly Fest 2013 (more by Dana (distortion) Yavin)
As mentioned, Yeah Yeah Yeahs singer Karen O was nominated for an Oscar for "Moon Song," the song she co-wrote with Spike Jonze for his film Her, which Arcade Fire's Will Butler and Owen Pallett scored (they're nominated too). It's since been announced that Karen will also perform "Moon Song" at the awards ceremony. U2 and Pharrell will perform too. The ceremony, hosted by Ellen DeGeneres, airs on Sunday, March 2 at 7 PM on ABC.
In related news, Karen just released another version of "Moon Song" which features a duet with Vampire Weekend's Ezra Koenig. You can stream that, along with the original version, below...
Karen O & Ezra Koenig - "Moon Song"
Karen O - "Moon Song"