I think one of the most important things the show said wasn't about whether or not people naturally have a set point where their weight is concerned or if an infection causes obesity, but in order to maintain their weight, people have to have a very accurate internal monitor. This monitor works well in so many people whether they are highly active or not.
My monitor is obviously broken. Whether it was because of what my mother ate during pregnancy, a virus, being taught poor eating habits, damage from carrying excess weight, I've resigned myself to the fact that if I want to keep the weight off that I've lost and continue to work towards my goal, I need to actively monitor my weight.
I am like the queen of losing weight. I've lost hundreds of pounds over my life with a range of different methods, and I always gain it back once I stop weighing myself regularly (hence my secondary title: "The Dutchess of Regain"). I've lost a significant amount of weight since May 2007, and managed to gain 20 pounds back effortlessly in the past few months by not monitoring my weight and eating what I see others around me eating. Because I kept planning to go back on my diet after the holidays, but kept making excuses (Mr. A. still off work, nasty ear infection, etc), I avoided the scale. I got on it yesterday, and I resolved that it might not be fair, but I have to go back to what works for me (my diet, more exercise, and continuing to monitor my weight and make adjustments).
I know what I have to do, and I am not absolving myself of responsibility, but the whole idea that it might not be a question of willpower or morality for either fat people or thin people is something I am glad was put out there by this show. There's a difference between that and saying that people are resigned to their fate IMO.