The last scene of the movie demonstrates that knowing that a pre-crime report was generated does allow the future to be changed (Burgess chooses to shoot himself, rather than Tom Cruise). The earlier plotline had suggested there was no way to escape fate - the protagonist ends up committing the exact killing he had been desperately trying to avoid (a la Oedipus Rex).
At the time the film came out, I was in a long involved argument about the theme of the film on screenwriting board.
There, I said:
"The issue of her predicting the future as it actually ends up taking place is more or less irrelevant in terms of the story the filmmakers chose to tell. That's set up from the very first precognition and subsequent raid. Agatha sees a murder that does not happen, because there is interevention. The premise underlying the story the filmmakers chose to tell us is that what she sees will in fact occur if we do not stop it. We are free to stop it, of course, but only because we know it is coming. If we didn't know, the world would continue on the rails it has been traveling on, and it would arrive at the destination Agatha has foreseen. This is the essential point that you have to buy into for the premise to work at all."
I dig a little deeper here, including analysis of the eye transplant scene. With a bit of a snarky tone, but I was arguing with friends...
