And it's beautiful, ingenious, thrilling, magical, etc. Fully deserving of the 89% Tomatometer rating (as of this writing), if not more. In fact, I'm a little tempted to hunt down the critics who gave it a rotten review and do them some bodily harm.
So Coraline is a curious little girl whose parents have just moved out to the country. Although they write books on gardening, they actually hate getting their hands dirty and are too buried in work to pay attention to her. She finds a mysterious passageway to a magical land which parallels her world but where everything is perfect. Or almost perfect, the only difference is that people have buttons instead of eyes and if she wants to stay she'll have to give up her eyes and let her "other mother" sew buttons on her. This becomes a cautionary (and kinda obvious) 'be careful what you wish for' story, and Coraline comes through with bravery and intelligence, with the help of a lot of strange friends--a Russian trainer of dancing mice, old ex-showgirls, a chatterbox geeky friend, and a cat. It's darker and a little more PG than you might expect for a kids story. This one is aimed just as much for the adults.
Without the visual flair, the story wouldn't be quite as impressive (although I liked the story in itself). This is a team-up of Henry Selick (The Nightmare Before Christmas) and Neil Gaiman (MirrorMask), so it's gotta be good. Visuals are hard to put into words. Just go see it already.
Oh, and a final note. The 3D was good, but not really necessary. There's a few scenes where the 3D gags work, but mostly it would be just as enjoyable in 2D. Also, 3D is not kind to the front row, where I like to use my peripheral vision. If you see it in 3D, sit at least a few rows back.