Software user interface design is a very important discipline, and one which Apple has recently revolutionised. Making things easy is notoriously hard, so screen ergonomics is an important and challenging topic. Investing in this book seemed like a very sensible idea.
Unfortunately, and astonishingly, this 600 page book has pretty much no actionable content. It is a high level descriptive romp through the subject at a superficial and occasionally facile level - for example, from a page opened at random: "Social media participation can involve 10 people in a chat room or hundreds of millions of discretionary users in an environment such as Facebook or Myspace." So what? The authors never seem to convert their rather uninsightful observations into any valid or useful recommendation for action. This is the sort of book for which the phrase "No s**t, Sherlock" was invented.
At the beginning of the book the authors list "Ways to use this book". I can recommend one more: put it on your bookshelf and point at it. That's about as valuable as it gets.