Some big names got up and performed yesterday in honor of Michael Jackson. Stevie Wonder, John Mayer, Jennifer Hudson, on and on. But towards the end there was a woman, seemingly unknown, who stepped forward and sang lead on "Heal the World" and a big role in "We Are the World". A lot of head scratching and "isn't she…" ensued. Rolling Stone has solved the mystery. Her name is Judith Hill and she is from Pasadena, California. According to Rolling Stone she was to be one of the backup singers for Jackson's upcoming shows in London.