FatWatch is directly inspired by Eat Watch, a Palm application developed by John Walker, author of The Hacker's Diet. It is a book that Mr. Walker makes freely available online, explaining the methods and reasoning he used to gain control of his weight and eventually drop from 215 to 145 pounds.
Mindless Eating: Why We Eat More Than We Think is an excellent book by Brian Wansink about how things like packaging, environment, names, and so on affect how much we eat. The book is full of descriptions of his experiments, which are a lot of fun to read. It's also full of tips on how you can make small changes to your environment (e.g., eat off smaller plates) that will reduce the amount you will eat.
The Skeptical Hypochondriac is a good blog to read if you're interested in health news but have a low tolerance for junk science.
CalorieLab Calorie Counter News is a blog that covers almost every diet and exercise related news story that gets published.