The taxonomy of social media is complex. Social media usually refers to Facebook, LinkedIn, MySpace, Twitter and other sites. But in its widest sense social media can be any site that networks of people, including newsgroups, listservs and sites such as YouTube. YouTube is still primarily a file sharing site but with the addition of comments they are now more social media than file sharing sites.
Blogs are also part of on-line social networks but are different from the other social media sites in two ways. One person may have several blogs, each focusing upon a different topic but it rarely makes sense to have multiple Facebook or LinkedIn accounts. The second is the concept of time. In social media sites, such as Facebook and Twitter, it is the NOW that matters. Businesses may care to keep a record for legal purposes but most users rarely care about what was communicated 24 hours ago (if not 24 minutes ago). Whereas, with blogs, the continuity of posts matters. They are not focused upon the here and now.
All strategies used in attracting clients and consumers must focus first and foremost upon these two aspects, especially the concept of time.