I don't have too much to say about The Hobbit: An Unexpected Journey, except that I liked it an awful lot. This is no surprise. While not a Tolkien scholar, I read the Hobbit and the trilogy several times in my youth, and have watched the Ring movies several times in my current decrepitude. This is what we like and plenty of it.
The tone is a little different from the Lord of the Rings movies. It is mainly dwarves, who are pretty silly. But there is also a more mythic tone, it seems to me, with more history, spirits and mystery.
However, I'm not really qualified to discuss this critically. Basically, I just wallowed in it.
I do have one minor complaint that I only mention because I don't think I've heard anyone else discuss it. It is the overdone trope of the wild cavern ride. You know the scene where the heroes are careening through an underground mine or cavern, maybe in a cart, like in Indiana Jones and the Temple of Doom? When I saw that, I thought, "This was put in the movie as an excuse to put a roller coaster in the eventual theme park." I mean, it was thrilling, but it seemed sort of stuck on.
I remember thinking the same thing during a similar scene in the Brendan Fraser Journey to the Center of the Earth.
We get one of these in the Fellowship of the Ring, with the Balrog scene, and it is certainly appropriate to the material. But there are like 3 of them in An Unexpected Journey. Enough is enough.
Still, liked this a lot.