Do Social Networks Limit Innovation?

In a recent article by the New Scientist, some researchers have suggested social platforms such as Facebook and Twitter “reduce diversity and keeps radical ideas from taking hold”. The larger the interaction (group size) the more likely you will run into people who will disagree and potentially deter you from pursuing it further.
Viktor Mayer-Schönberger’s suggestion? Smaller social groups and less interference.
It’s an interesting theory and one I can relate to at some level. Looking back, most ideas I’ve shared are more positively received by smaller groups. Fewer questions, objections and more constructive feedback.
This is where I get confused with such a study. Work, school, and even your baseball team are all social networks.
When you look at Facebook which went from a small Harvard project to over 252 million users and Twitter which shared similar success you’d expect innovation to then fall off a cliff. We’re more connected now than in any time in history and yet every day I stumble across a new and innovative idea. How is this possible?
Do the people who generate these ideas avoid social networks to nurture such thoughts? No, probably not. They did what the rest of us do — share the ideas with a select group within their social network who are more likely to be receptive.
In life, few people will ever see the world the way you do, no matter how great a thought or idea. So it stands to reason that the more connections you have available to you, the more likely you will be to share them with the right people.