As a long time Metallica fan I have listened to this band since I was a kid. I've been to many of their concerts from Ride the Lightning onward...
All of Metallica's albums have their highs and lows but this one is simply a "mature" album. You can hear the years of experience this band has. They have gone back to their roots and the roots of heavy metal. Tracks are reminiscent of giants like Black Sabbath and thin Lizzie. The final track on the album, innamorata, is very a la Iron Maiden epic and lasts over 10 minutes... fantastic job from the boys at Metallica. Bravi... my new favorite album and possibly one of the best songs ever in Innamorata!