OpenSocial is part of Google’s GData strategy and consists of a set of client and server APIs for usage in the development of social web applications that are deployed by end users of social networking sites into their individual profile spaces. These social networking sites are the ones that implement the OpenSocial Service Provider Interface and currently include Engage.com, Friendster, hi5, Hyves, imeem, LinkedIn, MySpace, Ning, Oracle, orkut, Plaxo, Salesforce.com, Six Apart, Tianji, Viadeo, and XING. Says Google, “the ultimate goal is for any social website to be able to implement the APIs and host 3rd party social applications.”

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The applications that OpenSocial’s APIs facilitate are essentially Google Gadgets that are ‘made social’ whereby “using standard JavaScript and HTML, they enable developers to create apps that access a social network’s friends and update feeds.” At present, over 23,000 different Google Gadgets exist as mini-applications for subsequent deployment in desktop, iGoogle, website and now with the launch of OpenSocial, social network website environments too. A large number of top-tier application developers have already committed to building social apps using these APIs including Slide and RockYou, both of which maintain significant numbers of deployed instances of their Facebook applications. The success and adoption of OpenSocial as an application development platform is evident in the stream of applications being produced.

For developers, the benefits of building applications according to the OpenSocial APIs are that they will be compatible with a large number of social networking sites without demanding that a new set of APIs be learned for each site utilized. This is when the most universal social networking procedural calls are concerned, and by which the scope of OpenSocial operates. For the social networking sites implementing the OpenSocial interface, OpenSocial acts as an adjunct to support a proprietary platform by providing a repository of site-specific procedural calls for developers that are part of OpenSocial’s core packages and which supplement a site’s proprietary packages that provide a site platform’s point-of-differentiation.

The most difficult task Google faces with OpenSocial is keeping its partners aligned for the purpose of continually enhancing the OpenSocial APIs. This is because participating social networking sites may be disinclined to contribute platform code improvements to the OpenSocial framework knowing that as a result they will be made available to competitors also part of the OpenSocial alliance, thus nullifying any competitive advantages that would otherwise be maintained in avoidance of contributing such platform improvements and instead keeping them proprietary. On the other hand, if platform contributions to OpenSocial could enhance the integration of a social networking platform’s unique points-of-differentiation within the alliance, then the entire alliance may be enhanced. Other hurdles Google faces is certifying the quality and completeness of OpenSocial Service Provider Interface implementations, and also showing that orkut does not unduly benefit from being an OpenSocial partner as a result of it also being a Google product. Facebook now has some reason to release a similarly conceived environment for providing non-Facebook social sites with an environment to deploy Facebook applications, but that is unlikely without a radical change in ideology, hence the launch of OpenSocial quite possibly marks the plateau of Facebook’s power (no matter whether it joins the OpenSocial alliance or not) and the rise of MySpace and the other OpenSocial partners on the back of the continued rise of Google.

Technical Reading
How To Build Your First Social Gadget
13 Power User Tips for OpenSocial Developers
Google OpenSocial: Technical Overview and Critique
OpenSocial Makes the Web Better