Panayotis Vryonis has this thoughtful argument about why what we call social networks are in fact social places, since networks are made of the people who actually use them. Here's the key insight for me:
If we consider Facebook, Linkedin, Twitter, Google+ and the rest social networking sites, places, user behaviours make much more sense.
For example, the reason most users use/need more than one of these places. Because they prefer to keep their social networks separated: They want to share their kids’ photos with friends, and they want to share content that’s related to their work (and probably boring for their friends) with their professional network. They want to make jokes with their old high school friends and they don’t want these jokes to be on the same place where their boss hangs out.
This actually helps us further understand why focused purposes actually enhance a strong sense of community. Once you call something "the place where you share your social life", that can mean a lot of things for a lot of people. Whereas the more specific you are (but not too specific, paraphrasing a well known Einstein quote), the less room there is for ambiguity, which increases the odds of everyone working towards the same purpose.
The lesson goes for social places but it also applies to products and everything we do in terms of communication. Aiming for the universe, it's quite possible we'll miss every single object in it.