As a marketing technologist, I've noticed interesting behaviors when marketers sell to marketers and salespeople sell to salespeople. Too often the tactics demonstrated are narrowly useful in one specific application.
I first heard about Traction while listening to some of my favorite podcasts. The author, Gabriel Weinberg, strategically included quotes from many influentials in the entrepreneurial space and seems to have used this as his own key channel for the book. In this way, the book serves two purposes: as a case study in the narrow channels for how best to produce and market a book, and the broad channels it outlines that apply to almost any business.
Highly recommended - especially at the price it's being sold for!