Note:This YouMoz post from Adam Carson discusses how social influence can be measured and tracked as a ranking factor. To learn more about Social Authority, the new Twitter influence tracking feature from Followerwonk, please read our post Social Authority: Our Measure of Twitter Influence.

With the official confirmation from Google and Bing that tweets are being used as one of many ranking factors, it’s only natural that marketers will be seeking insight on how they are measuring ‘social authority’ and who some of the top influencers might be.

Social Influence

Unsurprisingly, celebrities dominate lists tracking profiles with the highest number of followers. Stars and their teams are already looking for ways to take advantage of the broad and instantaneous reach of Twitter -- increased search exposure is simply an added side-benefit. Having a direct channel of communication with fans can be a great asset, but could prominent Twitter celebrities be asked, expected or even contractually obligated to tweet? Musicians with large numbers of followers like Lady Gaga and Kanye West can direct a lot of attention to current and upcoming projects, but with the right fit they could easily send fans to any sponsors willing to pay top dollar.

Just as they are required to attend premieres, sit though press junkets, and make talk show appearances, actors could be asked to tweet before, during and after productions. Professional sports leagues may frown upon in-game social media use, but big money sponsors have lots to gain from leveraging the Twitter networks of stars like Dwyane Wade, Tiger Woods and Chad Ochocinco. Deals like these with influential people are already affecting the Twitterverse and now by extension, the search environment.

Pay to Play?

The Oprah effect on books and other products is well documented; she can recommend almost anything and demand soars. This is one area where online authority and commercial influence presently converge -- how much might a favourable tweet from Oprah’s account be worth? It would be difficult to define exactly what constitutes a 'paid tweet' from a high profile account. Google and the U.S. FTC already have issues ‘policing’ paid posts as it stands, official admission that tweets do have some affect on SERPs will only lead to additional efforts to exploit the system. Will abuse be penalized? Will big brands be immune?

The Top Twitter Profiles: Who are the Influencers?

Just as in search, the exact algorithms will remain closely held, but there are a few account activity signals we can assume that Bing and Google are examining to calculate their takes on social/author quality, including follower ratios, user engagement, retweetability, and yes, maybe even PageRank (although I’d tend to agree with @SebastianX on that point):

If at all, I’d assume the PageRank of a Twitter profile is a minor factor when it comes to ranking a Twitter account’s weight / authority.

So, like PageRank, let’s just say that this post is for entertainment purposes only. :)

Top Profiles by Followers: The folks at Twitaholic have done the work for us, ranking profiles by number of followers. [Data from December, 2010].

Top Profiles by Retweets: Not without its criticism, Klout is a service aiming to measure online influence and they offer some insight into the users who are retweeted most often. [Data from August, 2010].

Top Profiles by PA: Obviously we don’t have access to real, granular toolbar PR but we can pull Top Pages results from Open Site Explorer to see who might come out on top in terms of link equity.

Paraphrasing SEOmoz: Page Authority is an amalgamation of all the Linkscape link metrics (number of links, linking root domains, mozRank, mozTrust, etc.) we have into a single, predictive score.

Discounting duplicates (Twitter URLs are case sensitive!) and going strictly by the numbers, OSE Top Pages returns the following as the Top 10 Twitter profiles: BarackObama, mashable, aplusk, addthis, twitter, simpleforum, stephenfry, cnnbrk, shitmydadsays and comcastcares [Data from December, 2010]. However, it's easier to see who's really leading when broken out into groups of individuals and publisher-type accounts:

By separating individuals from businesses and publishers, you can see how much these lists here differ from those above who lead by total number of followers, and it’s much easier to get a feel for the type of sites that are flowing link juice to these profiles.

Rather than altering current search and social media practices, this is more of an exercise in perspective when considering what these lists might look like in your own or your clients’ industries. Who are the top Twitter influencers in finance, travel, autos, politics, real estate? These individuals are a powerful subset of the linkerati, pushing and shaping the content read online each day, and now we have validation that their efforts do exert a greater influence on the web.