The act of rendering a search engine's results optimal by decreasing the rank of potentially negative results or bad press. Reverse SEO has become one of the most effective strategies for minimizing the impact of bad publicity within the search engines’ organic listings. It is an online reputation management (ORM) tool of SEO consultants who manage Online Reputation Management. Too often, companies become targets for negative press online. Angered customers start blogs to take businesses to task for grievances suffered, real or imagined. Dishonest competitors will often go to great lengths to distribute fraudulent reports online. The problem is that these blogs, pages, and reports can begin ranking well in Google and Yahoo
In my opinion Reverse SEO is a practice of doing SEO based on the highest ranked websites by following their site linking, keywords, meta tags, etc.