If you're thinking about buying this book, you are interested in the chemistry of food and have probably read Robert Wolke's "What Einstein Told his Cook" or Joe Schwarcz's "That's the way the Cookie Crumbles" or perhaps even the paragon of English-language food chemistry: Harold McGee's "On Food and Cooking". If you haven't, I recommend you start with one of those first ("Einstein" would be my #1 choice).
Why? Because those books are better written and about topics that are of more general interest to a North American audience. Molecular Gastronomy is unabashedly FRENCH - which is an excellent thing, but surprising if you're not expecting it. The foods it focuses on are French foods, the research it cites is French research, and I suspect even the translator has French as his first language. So, for example, this book discusses the "Perfect Sabayon" - a lovely culinary question, however one that many Americans (even "foodie" Americans) might find less interesting than the question of cookies going stale (as covered in Schwarcz). The translation is odd.... it is clear, in reading it, that it wasn't originally written in English. Some particularly French phrasing persists in the translation and I am also not convinced that the translator had as extensive a chemical vocabulary as was called for (for example, the phrase "vitreous transition temperature" is used, where "glass transition temperature" is the term used in most materials science texts).
As other reviewers have commented, the vignettes themselves may leave something to be desired. Each chapter is quite brief (Schwartcz's work is similar), so may not have the text to go into the depth a reader might desire. However, the real strength of this work is that it addresses interesting food/chemical questions that aren't being covered by the North American writers.... there's a lot of wine, cheese, and emulsified sauce in this book that you don't see anywhere else.