Worth watching for Chris Cooper, and not much else
I found this movie to be mostly a bunch of self-indulgent tripe (as usual) by Charlie Kaufman, almost as irritating as Shamalyan's Lady in the Water. The whole "metamovie" gimmick is overplayed and pretends to be much deeper than it really is. And for all the praise that Nicholas Cage gets for his performance, as usual he tries too hard and you can see him acting (or trying to act), as in his overhyped performance in Leaving Las Vegas. We get Cage as "Charlie Kaufman" channeling a parody of Woody Allen.
On the other hand, I still think that the movie is worth watching for Chris Cooper's performance. He switches from comical to pathetic to menacing so naturally that he was a joy to watch as Laroche. It's not surprising that his performance received so many accolades - he's what kept it from being a complete turkey. Brian Cox's brief appearance was entertaining too.