This handsome hardcover is interesting and entertaining since it's an anthology of the authors' secrets as revealed to their readers. It won't definitely be boring due to its artistically-designed fonts, colors, photos, etc. Therefore, it's quite costly (US$35) and I hope there would be a paperback edition soon. From its 69 authors, Alain de Botton is my favorite because I've enjoyed reading most of his books. As for some others I'm sorry to tell you I knew them vaguely, unable to find time to read them. For instance, Will Self, Ian Rankin, A. S. Byatt, Joyce Carol Oates, Audrey Niffenegger, etc. Moreover, there's another author, Nicole Krauss, I recall reading her "History of Love" some years ago.
While reading these various reflections, we can see this book try to present its contemporary authors inquired to say something about their 'secret' motives that ignite their writing passions. So I think many readers might admire this book, one of the reasons is that we can share their ideas or 'secret' ways our favorite authors have effectively applied in writing as professionals do. Indeed, writing is one of the four skills in any language that needs practice as well as inspiration, aptitude and possibly charisma. We know that not everyone can be a good and great author but this anthology would provide you some ideas, understanding or even tips of thought.
However, its overall readability is something you might find somewhere, I found some pages boring when I read unintelligible chunks of his/her writing reflections but I kept reading till the end. Therefore, I'd like to recommend some I like most to you: A Large Desk (Alain de Botton), A Cabinet of Curiosities (A. S. Byatt), A Body Plummeting (Nicole Krauss), A Purple Pen, a Portable Home (Elif Shafak), and Seahorses (Jill Dawson).
In fact, I think the editor might have the idea on this book's title from Bertrand Russell whose "How I Write" was published in 1956 (Routledge, 2009) and it's all right because it focused on "The Secret Lives of Authors". If you read George Orwell, I hope you would find reading his "Why I Write" (Penguin, 2000) still illuminating and inspiring.