Thanks to some excellent research by Search Engine Land’s Danny Sullivan (@dannysullivan), this is now official – links shared on both Twitter and Facebook have an effect on the SEO rankings of that site. Retweets, too.
Sullivan pitched six questions to Google and Bing. I’ve picked out the highlights for you below:
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?
Bing: 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.
Google: 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].
Do you try to calculate the authority of someone who tweets that might be assigned to their Twitter page. Do you try to “know,” if you will, who they are?
Bing: Yes. We do calculate the authority of someone who tweets. For known public figures or publishers, we do associate them with who they are. (For example, query for Danny Sullivan)
Google: Yes we do compute and use author quality. We don’t know who anyone is in real life.
Do you calculate whether a link should carry more weight depending on the person who tweets it?
Google: Yes we do use this as a signal, especially in the “Top links” section [of Google Realtime Search]. Author authority is independent of PageRank, but it is currently only used in limited situations in ordinary web search.
Sullivan concludes that:
In the end, it’s clear that Twitter data especially plays a role in web search, these days. Who you are is being understood. Are you a trusted authority or not? If there’s PageRank for pages, both search engines have a form of TwitterRank for people.
Meanwhile, retweets server as a new form a link building. Get your page mentioned in tweets by authoritative people, and that can help your ranking in regular search results, to a degree.