There is growing a body of academic evidence suggesting that social networks lead to more isolation, rather than communication and connections.
It's true that when you walk into a bar or cafe and see people all around the place on their own and interacting with digital devices, rather than the people around them, there appears to be an issue. It would seem that communication behaviours have changed. But is that really the whole story?
Most people I know use social networks to augment their personal networks, not replace them. A social network provides an easy way to keep in touch with people and to share information, but sitting in front of a PC or phone posting links to funny YouTube videos or retweeting a great joke does not replace real social interaction - getting out there and meeting friends and family.
Perhaps the academics claiming we are all about to disappear into an online communications vacuum are just publishing hyperbole in the hope that they draw attention to their research, getting themselves one step further towards a nice comfortable tenured chair?
In my own experience with using Twitter to bring neighbours together in London, social networks have been proven to connect people who would never have met in other circumstances. And there is one more Tweetup coming soon in London where I will be passing through London, between India and Brazil, so if you can make it then it would be great to see you there...