Would anyone out there be surprised to learn that the largest network for sharing information online ISN’T Facebook, but rather AddThis?

AddThis, the unobtrusive yet apparently hyper-magnetic sharing widget that allows users to email news stories and post to scores of other sites, has grown so prevalent online that it has now decided to share its sharing protocol with the world. OExchage (http://oexchange.org), establishes a common way for services like Google Buzz, Instapaper, Posterous, and others to receive and post shared content around a number of third-party sharing tools, all the while preserving users’ sharing preferences.

Hooman Radfar, co-founder and CEO of Clearspring Technologies, home of AddThis in Northern Virginia, told us in a recent interview of the strategy underlying the move, “It sounds corny, but some things you do just because it’s the right thing.”

And, with user privacy and opt-in serving as a lightning rod for consumer affairs ire these days, it certainly seems like the right time as well. Open Web leaders such as Digg, Echo, Google, Instapaper, LinkedIn, Microsoft, Posterous, PrintFriendly, Springpad, StumbleUpon, Webs.com and yfrog (Imageshack) have joined Clearspring in support of OExchange. Numerous products, like Google Buzz and Instapaper, have already implemented the protocol.  Clearspring’s OExchange release states, “This protocol, in conjunction with a number of others (i.e. XRD, OAuth, and others) enables, for the first time, a complete open solution for sharing content online.”

“The key to increasing the amount and quality of sharing online is smoothing out the user interaction. By simplifying the underlying mechanism for cross-site sharing with OExchange, people can focus on what they're sharing, rather than how, "said Chris Messina, Open Web Advocate at Google.

The “how” currently consists of: blogging, Like, translate, e-mail, save for later and print. Prior to OExchange, Clearspring said, sharing services each spoke different language or has a different integration scheme, making it hard for publishers to provide access to all these services. “OExchange solves this problem by defining an open protocol for third party sharing tools to discover and send content to these services,” Clearspring said.

In support of our opening statement, AddThis likely reaches upwards of 1 billion users, given its prior comScore measures of nearly 700 million users and its phenomenal rate of growth. More than 1.2 million sites have downloaded the free AddThis sharing tool.  It had nearly 300 services already integrated into its sharing “deck” – the choices that a user can just click to post a piece of content from the Web, to their own personalized accounts, as with Digg and Twitter, or to a range of popular, national “Facebook” clones in other countries. There were another 800 services awaiting integration when the decision was made to just open the protocol to any sharing service.

But adding the endorsement of Digg, Google and Microsoft would easily turn OExchange into a defacto Web standard. What makes sharing so easy with AddThis, will make it virtually second-nature for all Web users to click and forward content they find useful to their preferred social networks, or direct to colleagues via email. Once the user selects a site to which he or she shares content, that site automatically personalizes the sharing preference for the tool.

In our veiw, there are myriad implications of streamlining this user interface, but here are just three:

• All major search algorithms value content links in determining the naturalized search return ranking of information online. Publishers who have only focused on getting their links “syndicated” must give heavier weight to making their content sharable to social destinations. Consumers will prove a much more potent force in generating links to valued content than ever before.
• Clearspring can already anonymously measure what content is being shared and to which services. Its service directory ( http://addthis.com/services ) can already track which social services are trending up or down on the basis of Web users’ sharing activity. (And, yes, Facebook is still trending UP.) It’s not clear that Clearspring has any aspirations to kingmaker status – all the documentation on OExchange emphasizes the discoverability that sharing brings to valuable Web content. And, ANYONE can employ the OExchange protocol, so there's no gatekeeper or collective role envisioned. Still, once users have a means of controlling their sharing preferences, and sharing sites have the means to both track and report back on these preferences, both the knowledge base for what content connects with people and the places it is shared will have major implications for both content producers and advertisers.
• To put it bluntly, if Clearspring and others using OExchange can tell what content interests adhere to even anonymized users, can ad targeting be far behind?

Chris Saad, co-founder of DataPortability.org and vice president of product strategy and community at Echo commented, “To make the Social Web as Interoperable as the Document Web, it’s key to have strong standards for sharing information. OExchange is an essential step to continuing the inexorable march towards a peer-to-peer social network where every node is a first class citizen.”

OExchange, which is licensed under the Open Web Foundation Agreement. Information on how to impliment the protocol appears on the organization's site.