Here are several reasons this should not be made. First off, the original was strong enough to stand on it's own. It did it's own thing in it's own way and was critically acclaimed for it. The story doesn't need to be continued. I think you continue it is only going to weaken it. It's a money grab. It's not directed by the original director, however it is produced by him so I can't give it too much shit. I saw the trailer, and it wasn't good. Oh something wasn't there but now it is, how groundbreaking.
It's not hard to startle me which that trailer tried to do and even then it failed. They're gonna make the same movie again, and generally I don't like that.
I guarantee this movie is going to have an inflated budget that will do less than the original did both artistically and financially compared to the first one. This is gonna end up turning into Saw, I loved Saw, it was a great movie, good premise and told well. Now there are like fucking 7 of the damn things each one worse than the first. I hope, HOPE they don't do this to paranormal activity. What was once a brilliant movie that I loved will turn into Saw 7.