Saw this on Friday. While certainly not a favorite, I thought the acting of the two female leads -- Vera Farmiga and Isabelle Fuhrman (who play the mom and the title character) -- was well done.
The plot twist was pretty good too, though the ending was drawn out excessively This is not to say I was anxious for the film to end (I wasn't sitting there wondering if the movie was over yet), but it just kept on going.
"Many men, perhaps even most, are unhappy in their souls. We burn so hard, but we shed so little light; it makes us crazy and sad." - Clive Barker Galilee