I can't agree. It's background music; there's a good reason classical doesn't accept soundtrack as part of its canon. However, it's good for what it is, in part because it's derivative. I normally don't like the songwriter's work either but I think in this case Peter Jackson browbeat him into effectiveness.
That surprises me, normally wouldn't expect you to accept 'background music' as an excuse for something being half-assed.
Film soundtrack is not really high art; even still, here it could've been done better.
Its saccharine and repetitive; a handful of cheap emotional cues recycled verbatim over the course of 9 or so hours (?) of film. Only way to keep the proles reminded that its the same story they're watching, maybe.
I don't know what the story is in America but over here things like this seem to devour big chunks of orchestra's concert series programs; because the state funding bodies they live off expect them to do things to keep the idiots satisfied ("come see the music of the movies!!"). Seems a waste of great talent, and I can imagine a lot of amazing orchestral musicians getting very bored doing this.