Danny Sullivan a Contributor at Search Engine Land has interviewed over the phone and threw emails with Bing and Google Respectively.
He posted the results of his interview ” What Social Signals Do Google & Bing Really Count? ” and i highly suggest everyone to read it, Because in my opinion is a must read!!
In Conclusion, Bing and Google confirms that Twitter and Facebook influences SEO / Search Engine Optimization.
This Is a couple of Questions and Answers from the Interview:
1) If an article is retweeted or referenced much in Twitter, do you count that as a signal outside of finding any non-nofollowed links that may naturally result from it?
We do look at the social authority of a user. We look at how many people you follow, how many follow you, and this can add a little weight to a listing in regular search results. It carries much more weight in Bing Social Search, where tweets from more authoritative people will flow to the top when best match relevancy is used.
Yes, we do use it as a signal. It is used as a signal in our organic and news rankings. We also use it to enhance our news universal by marking how many people shared an article [NOTE: see the end of this article for more about that].
3) Do you calculate whether a link should carry more weight depending on the person who tweets it?
Yes we do use this as a signal, especially in the Â”Top linksÂ” section [of Google Realtime Search]. Author authority is independent of PageRank, but it is currently only used in limited situations in ordinary web search.
As you can conclude, Authority Of the person tweeting a link will have an affect on Bing and Google Rankings, but make note that it is one of the 100+ signals in their search Algorithm.