This is unofficial as of now, but here we go anyways:
Inside Gamer Online is reporting that the game is done, and has been sent off to the DVD production factory, where heavily armed guys are standing in front and inside a building making millions of copies of the game. With only 12 days left until the game hits US shelves, this is actually a bit late of an announcement, since Halo 2(coming out in November), was announced gold a few days ago.
Anyway, stay tuned for the official announcement from R* themselves.
Thanks to Planet GTA for the heads-up.