Ignore Orkut, OpenSocial, Yahoo Mash and Yahoo 360. Google and Yahoo have come up with new and very similar plans to respond to the challenge from MySpace and Facebook: They hope to turn their e-mail systems and personalized home page services (iGoogle and MyYahoo) into social networks.
Web-based e-mail systems already contain much of what Facebook calls the social graph — the connections between people. That’s why the social networks offer to import the e-mail address books of new users to jump-start their list of friends. Yahoo and Google realize that they have this information and can use it to build their own services that connect people to their contacts.