“What Would Seth Godin Do” is the unusual name for a wordpress plugin, but the plugin author has credited Seth Godin for the idea. I spotted this plugin at work on several blogs, so checked it out. Its based on Seth Godin idea of using cookies to distinguish between new and returning visitors to your site and offer two experiences to two different sorts of people.
What Would Seth Godin Do WordPress plugin is one of the ways to nudge new visitors to subscribe your feed. Once you activate the plugin on the Plugin Management page, By default, new visitors to your blog will see a small box above each post containing the words “If you’re new here, you may want to subscribe to my RSS feed. Thanks for visiting!” After 3 visits the message disappears. You can customize this message, its lifespan, and its location.
Remember that this plugin requires cookies and users without support for cookies will always see the new visitor message. Many modern browsers have options to delete cookies everytime you close the browser and also not accept cookies at all (privacy is a big issue nowadays). While an occasional cookie based prompt to subscribe may be useful; with cookies disabled browsers you may bug your visitors with a constant message to subscribe.
You can apply this plugin for more innovative purposes too and customize it for a better experience of returning visitors.