This book turned out to be a great gift for my food snob/ scientist dad. It tells you all the tricks you need to make a perfect steak/ fish/ broth and actually explains why they're important. I've found it incredibly helpful.
Good book to have when pondering over questions such as what would happen if, or how to best cook something and why. It is a great addition to anyone trying to build a decent food/cooking library. It is more of a reading rather than a "let's just follow a recipe" book and I would recommend it as a complement to other cookbooks. Should be a good match for Alton Brown and Robert Wolke readers.
@hugo: thanks! Both are useful. I'd say this one is good if you want the definitive best way to cook something basic (like a steak or stew) and learn principles you can apply elsewhere (e.g. how to think about searing meat). I certainly trust Bittman's recipes, but usually think of them as guidelines rather than hard-and-fast rules so I sometimes change the ingredients or cut out steps.