This excerpt form The Economist story:
"Both Google and Facebook are run like absolute monarchies in which hundreds of millions of users (digital serfs, some might say) have created identities. Rather like mercantilist countries in the offline realm, both companies operate policies to protect this asset. Google stoked the trade war because it wants to add what it calls a “social layer” to existing products such as picture-sharing and e-mail, making it look more like Facebook. It would help Google if users could bring their contacts to its services from other sites. But Facebook, the world’s biggest social network, wants to keep control of its serfs’ data and therefore stops them exporting contacts easily."