Leona Lewis -- season 3 winner of The X Factor, the British equivalent of American Idol -- scored her first #1 song in the U.S. this week with "Bleeding Love," which was the U.K.'s biggest-selling single of 2007. (She got a big boost here in the States by appearing on Oprah last week, and it's been reported that she'll perform on AI this season.) But her "Bleeding Love" success almost wasn't meant to be -- the song was actually written by Jesse McCartney for his upcoming album, Departure.

When Jesse dropped by 1515 recently, we chatted him up about how the song wound up in Leona's lap and whether he has any regrets about letting it slip through his fingers.

Watch more of our interview with Jesse here and then check back next week for an exclusive interview with Leona and a chance to listen to her debut album before it's released!