It seems that most companies stop collaborating as soon as they are at the firewall. There is an inside and an outside world. If something is done with social media, it is either internally or externally, however there is hardly any hybrid solution.
The big problem with the view of enterprises on the outside and inside world, is that the views are often static and people tend to treat the roles and people as static things as well. However these roles are continiously changing. Customers are becoming suppliers, employees are becoming partners. Companies such as Threadless, Lulu and Sellaband are the examples that there aren’t static roles anymore, nor there is a strict divide between internal and external. Lego has a design process that is both internal as external (external design process is powered by the Lego Factory).
If you can transform your business in a social business you will be able to be plugin into a bigger ecosystem and then you can participate in a network of networks. And as with every network, every new node will adds exponential value for the network and thus for your business.