As part of the promotion for This Is It, the documentary film about his final performances, an unreleased Michael Jackson single, also titled "This Is It," will be released on Oct. 12. The song is the first posthumous music to be released since Jackson's death in June, and features backing vocals by his brothers in the Jackson 5. The single will be released in advance of the film's official soundtrack, due out on Oct. 26, which will be a double album sequenced by the order Jackson performs in the film, and will feature different mixes of older hits. The movie is out on Oct. 28. [NME]