Many search marketing firms (including my own: http://www.chaosmap.com) stress the importance of inbound links to build credibility. They think in terms of the ‘authoritative sites.’
In most cases search engine optimization rarely addresses any other factors involved in the timeconsuming process of creating an authority presence. This is partly due to the fact, that most companies are unwilling to invest the amount of effort required. On-page SEO (code, content, structure) is important, but in highly competitive markets, you will not win the #1-3 positions race in Google without authority and trust.
The search engines links don’t raise your website to the authority level alone: inbound links are the result of being an authority.Websites that have achieved authority status will attract a substantial visitorship. These visitors actively check the content on a regular basis, discuss it with friends, write about it on their blogs and link to it in the pursuit of becoming authorities themselves. You’ll see references to these sites across the social media platform.
Inbound links are the major indicator that the search engines use to define authority, yet research shows that a human visitor considers a website an authority when the content is specific to the subject niche and constantly updated. Visitors also (without knowing it, perhaps) give higher ratings to an authority website that link to other authorities, to further the understanding of visitor regarding their search.
Google and the other major search engines recognize that authority websites link to other authorities.
Authority building is an essential aspect of search engine marketing (the technical analysis, strategy and recommendations). Social media marketing can be leveraged from both to help you maximize the potential of your website.