I see this inside organizations as well. I've worked for quite some organizations and one thing that strikes me is how small the number of connectors is in organizations. People that bridge gaps between individuals, teams, department, business units, office locations and the outside world. The interesting thing I find is that the size of the company matters a bit, but even in small companies the number of 'bridgers' is limited. Very quickly the social periscope goes down. People focus on their individual tasks, their team and maybe their department, but that's it. And, hey, I can relate. We're all busy right?
On the other hand, I do try not to give in. I do my best to share my work inside the company I work for and outside (by blogging and tweeting e.g.). I also try to connect to people, ask them what they are doing and actively listen to them. Maybe this is the most powerful way to reach out and bridge: by asking questions. Who are you? What are you doing? What are you happy and concerned about? Finally, on the more technical side I find there are great tools to 'reach out' as well. Twitter is one of them. It's helps me get out of my bubble and look around. Feedly is another great tool to subscribe and listen to topics that I'm interested in.
I'm curious if you agree we need more people that reach out. And, if you are actively reaching out, how you go about doing this. Let's connect here or over at your place!