This book seems to have received a HUGE amount of publicity, yet it simply states the basic principles I think most people are aware of : stay open-minded, keep all options at hand, don't get bogged down in the comfort of a situation that feels good, always be aware that it may disappear, forcing you to move on into unknown territories.
Actually, in number of pages, half the book is advertising for itself telling the reader why and how it was written and how some people have applied the principles it reminds us about.
However, the merit of the book is that does remind us, just in case we had forgotten, though life itself usually taps us on the shoulder or kicks us in the teeth every now and then, ensuring we don't forget.