Because email is an almost zero-cost way of communicating with customers, it's possible to create innovative marketing campaigns with instantaneous feedback. These help generate higher click-through rates, which means lower costs for customer acquisition. Godin cites numerous examples of effective direct marketing campaigns using email and the Web, including those of his own company, Yoyodyne Entertainment, which used online contests as an incentive for people to participate in marketing campaigns. One unique aspect of permission marketing is its focus on the consumer. Selling marketing data to other companies without the explicit approval of the customer is a violation of that consumer's permission, and it reduces the effectiveness of the campaign.
Permission marketing makes a lot of sense for companies with something to sell.
However, many Internet companies lack exactly that, which is why profit and the Internet often seem mutually exclusive. The core product of many Internet companies, including Yahoo, tends to be information. In most of Godin's examples, information is usually used as bait to attract consumers, but it's not the money-maker itself. How a company with nothing to sell could use permission marketing to generate revenues is not directly addressed in Godin's book, and is clearly one of the greater challenges for Internet companies. Overall, Permission Marketing is cogent, compact, and compelling, and Godin has put his money where his mouth is.