Earlier one could only guess the influence of social media on seo, but nothing was confirmed. However, it has been confirmed now that social media do play a role in deciding your page rank in both Google and Bing. In an interview with Danny Sullivan Google and Bing, both have confirmed that Twitter and Facebook has a direct impact on rankings.
Earlier many SEOs suspected that this may be the case but no one could really tell for sure. Though, it was evident that Twitter and Facebook shares and likes did help in getting more links to your site or page, which in turn helped your rankings. However, it was not known that the number of shares or tweets in Facebook and Twitter directly affected the ranking for those links or pages. Another important thing to consider is the social authority of person who shared or tweeted the link.
Number Of Times A Link Is Tweeted Shared Or Liked
So it is evident now that the number of times a link has been shared or tweeted or re-tweeted is considered as a signal and will affect the ranking of that particular link or page. Google and Bing have been very clear and have stated that they consider this as a signal in their organic and news rankings. People naturally link to or share links that they find relevant and helpful. Considering this as a signal will help to weed out spammy ways to manipulate the relevancy of a link and in turn manipulate the search results.
Author Authority Or Social Authority Of The Person Sharing The Link
Both Bing and Google have confirmed that they also consider and compute the Author Authority (Google) Or Social Authority (Bing) of the person who tweets. They look at signals like how many people you follow and the number of people who follow you. It will carry more weight if a link has been shared or tweeted by someone with more Author/Social authority; a lot like when you get back link from a site with higher Google PR. It is like saying, if people with higher authority shares or tweets your link, then the link must also be of higher value or authority and therefore should be placed higher in rankings.
An excerpt from the interview:
Danny Sullivan: 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.
So How Can We Leverage This To Help Our Site Do Better?
This is an indication of how important Social Media has already become in terms of SEO. Social media will not only help you get more visitors to your site when users share or tweet your link but will also help you fare better in organic rankings. Optimizing your site for social media is now a must. Focus on creating content that is relevant and is useful to the user. Provide a way for the user to easily share the page with others. Using of social media sharing buttons that lets user share at the click of a button is a good idea. Do not rely on the user to copy your page URL and to paste it on his Facebook wall. Instead, give him a convenient way to share your website pages. If you haven’t started optimizing your site for social media, you are already far behind. There is no time to walk now, it is time to run.