Bigger than the forming of the Foundation is the news that Yahoo has joined in on OpenSocial. For a reminder of who else is in, here's a shortened list: Engage.com, Friendster, hi5, Hyves, imeem, LinkedIn, MySpace, Ning, Oracle, orkut, Plaxo, Salesforce.com, Six Apart, Tianji, Viadeo, and XING. So, basically, out of all the social networks and web giants on the web, Facebook is the only one that's out of the loop - for now.
In the OpenSocial camp there is, of course, a lot of hand shaking, back patting and congratulating. Yahoo says they believe "in supporting community-driven industry specifications and expects that OpenSocial will fuel innovation and make the web more relevant and more enjoyable to millions of users;" MySpace is "setting new industry specifications for social web application development," while Google is reassuring us that "OpenSocial will be forever free and open.." All three companies will work on OpenSocial, everything will, of course, stay under the Creative Commons copyright license, and they've created an open source reference implementation called Shindig, available at incubator.apache.org/shindig/.