Great post, though http://www.blogcatalog.com that sends millions of visits a month to blogs and has an engaged community of bloggers from startup bloggers to pros should be on any list. BlogCatalog is the parent company of http://www.bloggersunite.org a site dedicated to harnessing the power of the blogosphere and another great site for bloggers to connect and get traffic and become more effective bloggers.
The term “organic traffic” is used for referring to the visitors that land on your website as a result of unpaid (“organic”) search results. Organic traffic is the opposite of paid traffic, which defines the visits generated by paid ads. Visitors who are considered organic find your website after using a search engine like Google or Bing, so they are not “referred” by any other website.