Just saw it tonight. It was very interesting, but not a great movie. To be honest, I knew what one of the twists was right at the beginning. I'd say more about that point, but I don't want to spoil it for the more astute members of the audience that will pick apart every little thing looking for Shyamalan's plot twists like I do. Shyamalan is always trying to make you think a certain way and he is rather deliberate with the evidence. He doesn't show anything that he doesn't want you to see. Now, I didn't start to figure out the "why" of the plot twist until halfway through.
I'd give it a 6 out of ten. It was very well done. Very well shot. It seemed to plod along at points while scenes were being set. I think the twist about the creatures in the forest was revealed too early. Kinda took a little of the magic and mystique away.
Bryce Dallas Howard was superb. Her performance really carried the movie. Everyone else was kinda like background only, not meant to stand out. Some would call the other performances nuanced. I think the dialogue was such that there was only so much the actors could do with their lines and roles. I think it was less nuance, and more struggling within a strictly limited range.
It was not at all the movie I thought I was going to see. In some ways good, in some ways bad. It wasn't scary at all. There are a couple tense moments where the more timid may want a hand to hold. But don't mistake this movie for the Exorcist or Alien. This is NOT a horror movie. It's a suspense movie.