Before we've even reached agreement on what Web 2.0 actually means, many are already trying to define future generations of the Web. A Google search for Web 2.0 nets 468 million results. Web 3.0 produces 211 million results. And Web 4.0 shows 154 million results. I don't even know what Web 3.0 and Web 4.0 are. However, I know that there are aspects of Web 2.0 that impact search marketing. Among them is social.