The article is presenting research of involvement in the internet communication, activities and creativity on social networking platforms. The comparative analysis of empirical data collected in Moscow, St. Petersburg, and Sverdlovsk is focused on digital communications intensity considered as an indicator of development of postindustrial social structures – networks and flows. The research reveals sustainability and wide spread of the internet and social networking platforms usage. However, the level of development of such new patterns of social life varies in different segments of society. Social structures revealed with the help of such indicators as involvement, activity and creativity in digital communications, are more developed in large cities and megapolises. Young people and the middle strata people are the leading groups in contributing to development of network and flow structures. Communicating on social networking platforms and generating intense flows of content, members of these social groups accumulate their virtual capital. Social differentiation based on unequal distribution of virtual capital is a new form of inequality. In relation to the inequality that was called the "digital divide" at the end of the last century, the new form appears as a digital divide of the second kind, where access to additional resources depends not simply on inclusion in communication networks, but on greater activity and creativity in them.