One relatively new factor that plays an increasing important role are social signs that come from social network site, micro blogging sites and social book marking services.
In 2010 major search engines like Google and bing have publicly acknowledged that social signs are another racing factor.
31% of the search marketers believe that social sharing of content will be a much more important means to improve rank this year than last year.
It has become more important in the 2012 and 2013 as it is making the marketers and website owners to understand how much traffic is going to a particular site.
