My biggest problem with this movie is, who cares!
Great film making isn't about style and cool shots, and Joel Schumacher defiantly seems to think so. For me a thriller has to work on one level, you the viewer must connect with the main character. Feel what he is feeling, go through what he is enduring. Place yourself in his shoes and experience what he is experiencing. Or else how can you as the viewer be thrilled, scared or moved.
Alfred Hitchcock is great at establishing this with his audience. Take any of the protagonists from any of his pictures, and you find yourself asking, "What would I do?" When this concept is applied to The Number 23, I don't find myself engaged in the plot enough to place myself there. I'd probably put the book down and find myself watching TV after. Not writing on walls, freaking out my family and all of the stuff Carrey did in this picture.
What we are dealing with here is eye candy. Stupid plot that carries us right through until the end, and it did exactly that. Good thing it all ties in with the main character, that this is his own personal demon and not some weird conspiracy. It makes more sense that way. It's not a boring movie, but it's defiantly not profound. Did I like it, No. Did I hate it, No. I just didn't care enough one way or the other.