While Google+ boasts millions of users, by many reports, it isn’t seeing the deep involvement found on other social networks. The Atlantic‘s Alexis Madrigal explores why that’s the case, comparing Google+’s planned community to Facebook’s more natural growth. The key for Google moving forward, he says, is to embrace the thriving communities that already exist around Google services like Reader and Scholar, rather than try to provide an all-encompassing umbrella. It’s not a new argument — Google was roundly criticized by heavy Reader users for integrating that service into Google+ — but Madrigal contextualizes it well, and despite briefly entertaining the idea that Google is merely using its social network to gain access to users’ demographic info, the piece favors new ideas over criticism.