Social Media Optimization (From Wikipedia)

Social Media Optimization (SMO) or Social SEO is the methodization of social media activity with the intent of attracting unique visitors to website content. SMO is one of two online methods of website optimization; the other method is search engine optimization or SEO.
There are two categories of SMO/Social SEO methods:
(a) Social media features added to the content itself, including: RSS feeds, social news and sharing buttons, user rating and polling tools, and incorporating third-party community functionalities like images and videos
(b) Promotional activities in social media aside from the content being promoted, including: blogging, commenting on other blogs, participating in discussion groups, and posting status updates on social networking profiles

Social Media Optimization is related to search engine marketing, but differs in several ways, primarily the focus on driving traffic from sources other than search engines, though improved search ranking is also a benefit of successful SMO.
Social Media Optimization is in many ways connected as a technique to viral marketing where word of mouth is created not through friends or family but through the use of networking in social bookmarking, video and photo sharing websites. In a similar way the engagement with blogs achieves the same by sharing content through the use of RSS in the blogosphere and special blog search engines.
Social Media Optimization is considered an integral part of an online reputation management (ORM) or Search Engine Reputation Management (SERM) strategy for organizations or individuals who care about their online presence.
Social Media Optimization (SMO), is not limited to marketing and brand building. Increasingly smart businesses are integrating social media participation as part of their knowledge management strategy (i-e. product/service development, recruiting, employee engagement and turnover, brand building, customer satisfaction and relations, business development and more). Additionally, Social Media Optimization is oftentimes implemented to foster a community of the associated site, allowing for a healthy business to consumer relationship.