Honestly, it's a slightly disturbing movie, but really informative about how the food industry is working in our country right now. The writers of this movie brought together a number of different people, such as Michael Pollan (In Defense of Food), Eric Schlosser (Fast Food Nation), and farmers, like Joel Salatin (Polyface, Inc.) and other people who have been seriously affected by the food industry and are now advocates for food safety.
Now you must keep in mind that this movie does have an agenda, so you do need to take it with a grain of salt, but there is truth in it. It's very revealing about how food companies operate, how they treat their workers, animals, etc. It is definitely something people need to start considering: knowing where their food is coming from, how it's being obtained, how far it's travelling, etc. Also, in a nation where our economy isn't doing so well, supporting local farmers will help to boost local economies.
You don't need to become an advocate for food safety or for eating organic, but it is important to know about your food, especially since it's the fuel you use to run your body. Be aware, and don't be left in the dark.