Soph and I saw it in 3D. I was actually impressed. It's true stop-motion, there is a light jerkiness in the framerate that makes it feel more authentic. Which I am a huge fan of. Yay traditional animation, boo CG.
This isn't a typical Disney/Pixar romp through the tulips. It's very moody, relies heavily on colors, shapes, and angles. There are (sometimes, blatent) adult themes, concerning death, birth, neglect/abuse, and sexuality. It still is a children's movie, but it's more like grimm fairy tales than a typical aesop>disney adaptation. A few families had to leave during the movie because the children were afraid of the imagery.
It's easy to see why people think Burton was on this; it looks IDENTICAL almost to the James and the Giant Peach movie. I thought it resembled JatGP more than Nightmare before Christmas honestly. It's creepy/moody, but not OVERTLY. And in fact, some parts are simply downright pleasant to look at.
The 3D effect was very nice. They used it mostly to demonstrate spacial elements than in the typical, campy, "oh no thing comin out da screen to grab you :O!!!!!" way. So a hallway would actually appear LONG or the characters would seem closer/further away. It was a nice gimmick.
Anyway, check it out if you can, I recommend this movie :3