First came its support for OpenSocial and OpenID. Now Yahoo has unveiled a strategy it's calling Yahoo Open—a plan not only to unite the brand under one umbrella, but also to allow third-party developers access to all the disparate properties. Currently users move from search to del.icio.us to Flickr to mail without any commonalities other than one login and password. It's almost as though Yahoo has built their social network in reverse by acquiring destination sites first and leaving the user interface for last.