Social networks are not new. The explosive growth of external social networks is rather breathtaking. There's more going on than a business plan though. Social networks reveal a lot about an organizations employee base.
It's smart business to do what Bank of America and Whole Foods have done with their customers by creating an online community specific to their brand. But more should do it internally. Losing a customer because you were not connecting through a blog is one thing (loss of revenue, cost of acquiring a new customer). It's even more frightening when it's an employee.
The alarming part, for some organizations is when the discovery is made around their own social network. I mean the employee base. There are a number of companies that think social networking is translated into LinkedIn, Twitter or Digg. But as great as those tools are, they're not as powerful as your organization's own internal social network.
Some might say; "we don't need to have an intranet site for social netowking." You have a community and it's ebbing and flowing before your very eyes, whether you know it or not. Could be organizaed or could be fragmented. My friends over at Webbed Marketing specialize in building online communities, but they can't create what your leadership can't see-vision.
The take-away is; your people crave community. And they'll find a way to connect. The question is whether you (the organization) want to be out front in providing the path.