Do you want to know...what...it...is?
(Via Living On Earth.) For an entertaining, somewhat basic overview of the problems caused by large agribusiness on commercial meat production, head over to themeatrix.com (requires Flash).
If you find yourself interested in this topic, I highly suggest the book Fast Food Nation: The Dark Side of the All-American Meal, written by journalist Eric Schlosser. Be forewarned, however, you may never feel the same way about that McFatty Burger you eat when you find out under what disgusting conditions the meat is produced and how that delicious flavor is engineered and added to the food.
I'm not vegan and I'm all for killing animals. Meat is just disgusting.