On the social networking side, OpenSocial has the cooperation of some 20 social networks, including MySpace and LinkedIn, which have agreed to support applications built with the OpenSocial APIs. Developers have created nearly 8,000 OpenSocial applications.
Microsoft isn't so much trying to layer applications on top of social networking sites as much as it is trying to allow Windows Live users to unlock the vast amounts of data they have and use it across social networking sites.
Despite the drive by both for more openness, social networking pioneer has not agreed to participate in either effort.