Ahhhhh. It's official: the Foo Fighters and HBO are finally letting us know when we can start watching the Dave Grohl-directed documentary. The Foo Fighters eight-part documentary series "Sonic Highways" is officially scheduled to premiere Friday, October 17th at 11:00 p.m. on HBO.  Directed by lead-singer Dave Grohl, "Sonic Highways" follows the Foo Fighters as they record their upcoming album.  They visited legendary studios in eight different cities across the country -- Chicago, Austin, Nashville, Los Angeles, Seattle, New Orleans, Washington DC, and New York.  The band calls it a "love letter to the history of American music" on top of a behind-the-scenes look at their "most ambitious album" yet.  The new record, however, still doesn't have an official title or release date, although it's expected out this fall.