The actual documentary will make up only part of the 2-DVD set.  According to a posting on the band's website, when the DVD arrives in stores on January 25th it will include 7 hours of bonus features including 40 additional scenes, "Exclusive Intimate Interviews with Metallica about the film", highlights from festivals and premieres, two separate audio commentaries by the band and the film's directors, as well as two trailers for the film and a music video. 

That may not be all, as the posting closed with these words "More info coming in the next few months. Stay tuned!" 

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