Just saw it tonight. It's fun, especially if you're into ghost stories. The scares are cool and mostly in camera. The build up and atmosphere are great.
I will say it is difficult to be at home alone tonight, as I can't stop thinking about the movie. Just a little while ago, I'm sitting reading some web sites, with my cat on my lap and a loud noise goes off behind me. Just turned out to be an empty box I had precariously stacked on some other stuff, but DAMN, creeped me the hell out.