Written by a professor who has collaborated with numerous social networking companies and is a member of the OpenSocial Foundation, this first book on the open source platform aimed at helping developers build social networking applications that can be deployed to multiple networks/containers provides tutorials and advice on how to use the platform's Client- and Server-Side APIs as well as approaches to addressing technical hurdles in the successful development and deployment of such applications. After reading this book, you'll get a good idea of what attributes are common to successful social networking applications, what social networks support OpenSocial and to what extent (for example, many support version 0.8 of the Client API but -- at publication time -- only hi5 supports the RESTful Server-Side API), what tools and architectural designs you can consider using to help you test, monitor, and make your application secure, scalable, and performant. As a bonus, you'll also get good information on emerging technologies from Sun and Yahoo that could take OpenSocial's "write once, deploy everywhere" goal to the next level of convenience.
The book provides plenty of code examples showing you how to use the Javascript Client API but only a few examples of what you can achieve with the RESTful Server-Side APIs and all of them are coded in PHP, a potential negative for some readers (libraries for Java, Ruby, etc are available for the server-side APIs, however). Also, while some of the tips are quite good, many could have benefitted from the use of better or more extended examples than the brief discussions provided (for example, the one on database sharding, an increasingly popular share-nothing architectural approach to data storage and management that's especially relevant to high-traffic websites, is intriguing but discussed only briefly; similarly, the discussion on scalable user interfaces was somewhat short on details and left me wondering about the practicalness of the recommended approach). Finally, a lot of the materials in the book can be found elsewhere easily (if you're willing to spend time finding them). Overall, however, I do think the book provides good value and am giving it a rating of four out of five stars.