https://edition.cnn.com/2010/TECH/04/22/facebook.won.the.web.cashmore/index.html?iref=allsearch

Google dominated the web in the era of interlinked Web pages. Every link from one Web site to another counted as a vote, determining the most relevant pages for any search term. The result: An unbeatable search engine.

Except that links between Web pages are no longer the most abundant source of relevant recommendations. Instead, people are sharing links with friends on social networks such as Facebook and Twitter. Now Google is paying those sites for access to public updates, but it lacks key data that would allow true personalization of search results. Google doesn’t have a complete list of your friends, combined with a list of their interests. Facebook does.

Source:  CNN (Pete Cashmore)

Facebook has proven to be a powerful tool.  In just six short years, we have seen it go from college students only to having over 400 million users worldwide.  The growth has been exponential and there is no end in sight.  Users have shown that they are willing to align themselves with products and services, and are receptive to the sales messaging.