You can view the full trailer for the game at metallica.com.
Here is a link:
http://www.metallica.com/index.asp?item=601748
This was posted on metallica.com on 12/14/08:
Metallica . . . Guitar Hero . . . It's Official!
12/14/2008
Yes, we know, it's the worst kept secret in rock-n-roll but we're here now to finally confirm that there will indeed be an all-Metallica Guitar Hero game released in the first half (!?) of 2009. Guitar Hero Metallica allows you to play as us in either single instrument or band career game modes in your choice of some famous settings (Tushino Airfield anyone?) or new venues with in the round staging. Included are 28 Metallica songs along with a few from some of our buddies like as Alice in Chains, the Foo Fighters, Slayer, Machine Head and Queen. There is also an all new Expert+ difficulty setting featuring two bass drum kick pedals (!!!) along with all the gameplay modes from Guitar Hero World Tour.
Over the next few months, we're going to be updating you with track listings, more features, of course how and when you can get the game, and some cool previews of the game right here on the site. As you've heard us say before, keep checking back for more details!
There is info on the game at guitarhero.com.
Here is a link:
http://hub.guitarhero.com/#/AllGames/metallica
On Guitar Hero's website, it says it should come out Spring 2009.