In the latest issue of Total Film (via io9), director Peter Jackson discusses how The Hobbit: An Unexpected Journey presented some very different challenges than The Lord of the Rings trilogy:

"The Hobbit is very much a children's book and The Lord of the Rings is something else; it's not really aimed at children at all. I realized the characters of the dwarves are the difference. Their energy and disdain of anything politically correct brings a new kind of spirit to it. And that's why I thought, OK, this could be fun!"

Peter Jackson also talked about the particular challenges of portraying thirteen dwarves as distinct characters:

"That was something I worried about. I imagined 13 guys with long hair and beards and I thought, 'How are we ever going to know which dwarf is which? It's an ensemble from hell really. I thought nine members of the Fellowship was a problem; but here, with Bilbo and Gandalf, we've got 15. It's working out fine though. The dwarves give it a kind of childish, comedic quality that gives us a very different tone from The Lord of the Rings."

Even though The Hobbit films take on a different tone, Peter Jackson assures it all feels like one large story of Middle-Earth:

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"I want it to seem like we've gone back on location into Middle-earth; that these two movies feel like they belong at the beginning of the other three. We're the same filmmakers going into the same world."

Peter Jackson's wife and writing partner Fran Walsh adds that the second Hobbit movie will be primarily focused with what the article describes as "war, madness and dragon rage." She explains:

"We always saw The Hobbit more in the golden light of a fairytale. It's more playful. But by the time you get to the end, Tolkien is writing himself into that place where he can begin that epic journey of writing LOTR, which took, as he put it, his life's blood. All those heavier, darker themes which are so prevalent in the later trilogy start to come into play."
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