Friendster.com announced the launch of OpenSocial applications on their social network today. This will allow any application created using OpenSocial to be used directly on Friendster!
Friendster announced their own API last October. There will be no apparent difference to users between an OpenSocial and Friendster application, as both will be supported.
Open Social is a common API for social applications across multiple websites. There are many websites implementing OpenSocial including hi5, MySpace, LinkedIn, Ning, orkut, Hyves, imeem, Oracle, Plaxo, Salesforce.com, Six Apart, Tianji, Viadeo, and XING.