I was pretty exited when I first heard about Knowing. I have always been a fan of sci-fi flicks and it looked promising. The concept is fairly original with the whole predicting the future with a note.
The first thing I reacted on was that the movie felt as though it was trying to be to many things at once. At one point it felt as a horror, then a sci-fi movie and then over to a disaster movie. Personally they could have dropped the horror elements and focused more on the two other genres. This would have made the movie more seamless. Secondly they could have picked better child actors. Their characters where not very believable and the dialog was very unrealistic.
I would also like to comment on the story. It is clear that it was inspired a great deal by religion. That is not a bad thing in itself, and I enjoyed the ending quite a bit. The aliens could just as easily been angels, it depends how you look at it. But there were way to many plot holes and situations that were totally unrealistic. One example would be the subway scenes, or how the phone service is working/not working every 5 minutes. I liked the beginning and ending more than the stuff in the middle.
Knowing is not a bad movie, it has its moments and is entertaining to watch, but do not expect a masterpiece. It is to bad really, because it had great potential. My personal rating is 6/10