I've read it, to be honest I thought it was a very lightweight. It's less than 200 pages of which about 1/3rd are images and set in about 14pt type, so very short on content. Has some good tips on the basics but didn't teach me anything new, felt a bit like it was clumped together from various blog posts. However it does cover good practice for approaching design briefs so maybe a good checklist if nothing else.
Most useful design book I've read recently is 'How to Run a Successful Design Business' by Shan Praddy. It's not light reading by any means but really focuses on the practical and business building side from a designers perspective. Highly recommended for the self employed/ design business owners.