I first became aware of this story when NPR had to issue a disclaimer before they reported the ADM price fixing scandal because ADM is a major contributor to NPR. Later, there was an excellent "This American Life" episode that covered the story.
To begin with, the idea that a global conspiracy, worth billions of dollars, to fix prices, was based in a crappy little town in downstate Illinois, always amused me. And that ADM has so much influence over people's lives, yet most people have no idea it even exists.
I thought the movie was great, with especially good performances by Matt Damon and Scott Bakula. Since I've been fascinated with the story for a long time, there were no real surprises for me, I knew everything that was going to happen. Nevertheless, much like Apollo 13, I was on the edge of my seat the whole time. If you see this movie without knowing the history, some of it may seem implausible. But it followed the true story pretty closely. And even left out some of the crazier, funnier incidents.
Overall, a nice combination of suspense and comedy. With some subtle little things thrown in that you may get a kick out of, if you're familiar with downstate Illinois. I also strongly suggest everyone check out the Ira Glass link I posted above.