While I had issues with The Hobbit: An Unexpected Journey for its flabby storytelling, the film has set the box office on fire and I did at least appreciate lots of choices in production design. These two featurettes from MovieWeb and SoundWorkds provide little looks into the visual effects and sound of the film.
The above VFX featurette focuses a lot on the motion capture animation behind the trolls in the film as well as the big caverns full of goblins. As for the sound featurette after the cut, it's a broad look at creating the sound and score for the film. I'm assuming the eventual featurettes on the DVD/Blu-ray for The Hobbit movies will be meatier and go into more particulars.
The Hobbit: The Desolation of Smaug and The Hobbit: There and Back Again will be out next December and the December after that. Then in 2015, Peter Jackson will release a new Tintin film, which he shoots the motion capture for some time next year.