If you're only going to read one book on leadership, this is a good choice.
If you're going to read more, perhaps it isn't. I'm not exactly well read in management books, but the advice about categorising work matched GTD, the advice about meetings matched The McKinsey Way, and the discussion of 'monkeys on backs' is an unattributed reference to a classic HBR paper. I'm sure there's a lot more like that.
I guess this isn't a bad thing, as the book is dense and provides a kind of one-stop-shop for leadership advice. I'm pretty sure some of it's original research too.
So, what is this book about? It's reasonably no-nonsense and happily actionable advice on how to act like a leader. The big messages are that leadership is about being an extra effective 'you', rather than normalising all characteristics, and that learning leadership skills is something that happens over your entire career, not just at the senior level.
The nuts-and-bolts approach is very welcome after much content-free waffling elsewhere about what leadership is. The book is divided into three sections, covering leadership at the junior, middle manager and senior levels. This does mean that the majority of the population could happily lop off the end of the book and lose very little, but it's dense enough to have plenty even in the first third.
I'm a bit wary of this book, but I think it's really because of the amount of content. I'm used to management books which are all about keeping it simple. This book is no exception in terms of the advice it gives, but there's so much of it that I despair at how much I've forgotten already.