One of the major blockbusters opening in Australian cinemas this Boxing Day is Peter Jackson's The Hobbit: An Unexpected Journey, the first of three Hobbit films to be released over the next two-and-a-half years.

For music nerds, word of the masterful Neil Finn being delegated the task of writing and recording the main song for the film is just as exciting and today we have seen the song premiered, thanks to Rolling Stone.

Listen to Song Of The Lonely Mountain now.

There'd already been Oscar-talk about the track before anyone had heard it, and that chatter is set to grow now that the composition is in the public domain and the film's release approaches.

The song was written after Finn was in a "dwarven state of mind", at the suggestion of Jackson and his crew, and recorded with his sons Liam and Elroy Finn. The initial melodic idea stems from an early scene in the film where the dwarves are singing in a dark and mysterious way, Finn says.

Dave Fridmann finished the song off, mixing it in his own incomparable style while allowing Finn his constant request for "more anvil". You'll know what that means once you've heard the song.

The soundtrack for the film will reportedly be released in December.