According to Pitchfork:
To help guarantee a world-class effort, Jeff Tweedy and Co. invited Feist up to their Chicago studio to record vocals for a new Wilco song called "You and I", Rolling Stone's Smoking Section blog reports. "Feist and the dudes in Wilco met at the Grammys last year, and she hit it off with everyone," Smoking Section says. "She's a Wilco fan, and the guys love her music, so they've kept in touch over the past year. Mr. Tweedy is a huge fan of duets, and wanted to work a duet into the new album. Feist was their first call. Everyone who's heard the song has been 'blown away.'"