More battle lines are drawn: Yahoo backs Google's OpenSocial

On the same day Microsoft announced new interoperability deals with five social-networking sites, Yahoo announced it has joined the Google-backed OpenSocial social-networking intiative.

Yahoo announced on March 25 that not only had it joined the OpenSocial group, but that -- along with MySpace and Google -- Yahoo also would create the not-for-profit OpenSocial Foundation "to ensure the neutrality and longevity of OpenSocial as an open, community-governed specification for building social applications across the Web."

When Google and a group of launch partners announced late last year their plans to create a set of open social-networking application-programming interfaces (APIs), the move was viewed by industry observers as a counter to Facebook's decision to make its development platform more open to developers.

Not too surprisingly, Microsoft was not and still is not an OpenSocial backer. (Nor is Facebook, in which Microsoft invested $240 million last year.) But a couple of the social-networking vendors who signed contact-sharing deals with Microsoft that were announced on March 25 -- specifically, Hi5 and LinkedIn -- are OpenSocial backers.

Yahoo is making a lot of"open" strategy moves, as of late, that probably aren't sitting too well with suitor Microsoft. Yahoo's backing of the Google-centric OpenSocial initiative is one more.