The book shows use that physicists' ideas aren't just flights of fancy, there are real contraints that have to be satisfied, in particular predicting why particle masses are what they are and not hugely greater. It also shows why the Large Hadron Collider, coming on line next year, is so important.
A word of warning though if you are starting from a position of not having read about the subject before. Although the work is non-technical, there's a lot to take in in this 500 page book, and you might find yourself struggling to keep it all in mind. I feel that the book doesn't have the sort of structure which allows you to read it in parts with breaks to assimilate what you have learned, and it might be better to start off with shorter books on the subject.