Where the Wild Things Are is a good film - I want to say that up front. The monsters are visually delightful. Max Records gives an utterly natural performance. The voice-acting (especially by Forest Whitaker and Lauren Ambrose) is perfect.
What Where the Wild Things Are isn’t is a kids movie. This film is about children, not for them. Spike Jonze and David Eggers apparently drew upon their own childhood experiences to write the adaptation, and the resulting script says a number of incisive things - about the somewhat loose grasp children have on reality, about the trouble they have figuring out how to interact with the people around them, about the things they see and understand as important without fully grasping what they mean. This approach means that the film is tense, sad, and occasionally violent in a way that I don’t think young children will like or understand. (Carol is the main wild thing, the physical manifestation of Max’s impulsiveness, and he’s responsible for a puppet-on-puppet savagery that made everyone in the theater - myself included - gasp.)
I liked Where The Wild Things Are, and I respect the artistic credibility of Jonze and Eggers’s adaptation. But weirdly, I don’t think I like it as much as I like the trailer, which is one of the finest examples of the form I’ve ever seen. It’s a two-minute dose of wondrous exuberance, unencumbered by emotional subtext, and while the film matches its tone once or twice, it never manages to achieve quite the same effect.