Indeed OpenSocial is definetely not dead. Although the OpenSocial spec has started as an alternative or competitor to Facebook platform to be used in consumer oriented social networks, the spec and accompanying open source implementation Shindig evolved into a more general API framework and a common data model which adresses use cases from consumer to enterprise portals and groupware solutions. While Facebook platform dominates consumer web and may be a natural choice for external identity support or content distribution, OpenSocial is being used inside ever increasing products and integrated to various cloud applications.
Current work in progress spec version is 2.0 and an active community discusses several new features that contribute to building a more open social web. You may see what is being developed here (http://wiki.opensocial.org/index.php?title=Spec_Changes) or join the community to monitor progres or contribute to the spec here (http://groups.google.com/group/opensocial-and-gadgets-spec).
Regarding your use case, OpenSocial may help you by supplying a client side JS based mash up container. With recent Open Ajax support and a JS container, OpenSocial (and Shindig) may easily serve as a dashboard or client side portal. We could sucessfully developed on top of Shindig a self service portal that can integrate gadgets from third parties or of our own developed ones. The Rest API also helps in developing server side applications.
So I strongly recommend to look deeper in OpenSocial for your specific needs.
