Metcalfe’s Law - Wikipedia
Google+: Doing too much to succeed? – by Emily Vraga
It’s easy to blame Metcalfe’s law on Google+’s slow growth (not in absolute user numbers, but in relative content numbers), however I think much of that is attributed to the slow openness of the G+ API. Certainly, the network effect level of Metcalfe’s law was horribly evident at G+’s onset, but the explosive growth of users, followed by the built-in network of Google services is starting to render that point near moot. However, comparisons are still being generated relative to the growth of Facebook. It bears worth repeating that Facebook’s growth took off when 1) it was opened to everybody 2) Facebook Connect (2008) laid the groundwork for the Open Graph Protocol (2010).
G+ has started to amass network effects especially since it, too, opened to everybody last month, but the it lacks an integrative platform much the way Facebook already does. There are a lot of disenchanted Facebook users who haven’t fully made the G+ switch because it lacks some of the prototypal features of Facebook. Until that happens (which it ultimately will), it superficially appears Google is just trying to match Facebook and Diaspora*, but I think it will be a couple of years until G+ is more than just a cross-posting platform.
Facebook, Twitter… they all took several years before the growing mass of users figured out how to make the medium the message. To people who are not typically early adopters, patience is a virtue.