Strengths Finder 2.0 is actually more than a book. It's a test.
Don't concern yourselves. There's no study required. You read the introduction of this book and set aside 20-30 minutes for an online test. Each book comes with a code for you to submit. (That's probably the only downside, as others can only take the test if they buy a copy of the book.)
Once you take the test, you receive results. What kind? Where your strengths lie in a set of 32 different areas. As I recall, mine were being ridiculously handsome and full of wit.
The premise of this book is that if we work out of our strengths, instead of always trying to improve our weaknesses, we'll be much more fruitful and content in our work. There have been studies which show our weaknesses have a ceiling and will only rise so far, but our strengths can be improved exponentially.
The rest of the book contains descriptions of each strength, what it looks like, and how to get along with those people. An obvious benefit to something like this would be in setting up a team. Knowing who to hire to help improve the team could be a real game changer.
The only thing that would make me appreciate this book and test even more would be going beyond your top 5 strengths. Because that's all they reveal. I would appreciate knowing the rankings of the rest. Knowing which area landed #6 and which landed #32 will make a huge difference in how I approach that area. #6 deserves to be worked on, while #32 can be blissfully ignored.