Early 2006 to till the date, there is a huge debate on counting performance for no-follow and do-follow backlinks for SERP algorithm. Now the point is why I am pulling the topic once again?The simple reason is while Google confirms they are calculating 200 signals with 50 variations for their SERP algorithm and Social networks signals playing a one of the vital role!
The concept for the specification of the attribute value nofollow was designed by Google’s head of webspam team Matt Cutts and Jason Shellen from Blogger.com in 2005. Question:What is “no-follow” links?The nofollow attribute value is not meant for blocking access to content, or for preventing content to be indexed by search engines. The proper methods for blocking search engine spiders from accessing content on a website or for preventing them from including the content of a page in their index are the Robots Exclusion Standard (robots.txt) for blocking access and on-page Meta Elements that are designed to specify on an individual page level what a search engine spider should or should not do with the content of the crawled page.
<a href=”http://www.example.com/” rel=”nofollow”>book stores</a>
So no-follow links basically introduced by the Google and to reduce the spammers from the blogs and if some one do-not use
no-follow for out bound linking then the Google PageRank(In the general case, the PageRank value for any page u can be expressed as:
i.e. the PageRank value for a page u is dependent on the PageRank values for each page v out of the set Bu (this set contains all pages linking to page u), divided by the number L(v) of links from page v.) will be passed to the linking website.
Sow the points comes that how much important is PageRank for ranking algorithm? If you think about Google still high PageRank and relevant natural links are most power full one for SERP algorithm.But when Google officially confirms that Google is counting social networking links for SERP algorithm(though we all know from the beginning of 2010 Google is looking for social network links specially Twitter accounts and tweets!)
We know all the social networking links are no-follow links; though think about that Google is still counting..that means Google give a good weightage for “no-follow” links.
Another point we can see that guest blog links(author bio),blog comment links are (most of them) are “no-follow” but Search engines calculate that for SERP.So for SERP algorithm valuable “no-follow” links are one of the parameter for Google and Bing specially.
When we are getting links from a valuable valuable website and that might be “no-follow” all the search engines giving a preference for search engine ranking algorithm and its proven that if you are linking to valuable “no-follow” links much better than less valuable do-follow links.