The information comes from Lev Chapelsky, general manger of Blindlight, a company that helps game developers contact and work with members of Hollywood's talent pool. Chapelsky said McCartney's single is due to debut "soon after the game is released," and since we're a month away from Destiny's September 9 release, there shouldn't be much of a wait left.
The NYT reports that McCartney's fully-orchestrated single was recorded at Abbey Road, with Giles Martin directing a 120-piece ensemble. Lady Gaga and U2 producer Mark Stent also handled the song's sessions. We'll all have to sit tight to hear what it actually sounds like, but we imagine any potential lyrics might go something like this:
Yesterday, alien life seemed so far away
Now I must convince them not to stay
With a laser blast to the face