Social Media in the Corporate Environment: an opportunity or a threat?

On Monday night I asked my followers on twitter "Can anyone tell me how many companies in the FTSE 100 use social media to engage with their key stakeholders. Rather promptly (that's why I love twitter) a follower of mine replied "Not many. Think it is less than 20 percent who use Twitter (saw the stat somewhere), but not sure about social media as a whole". We then debated for hours, over twitter, about the risks associated with using social media in a corporate setting. What surprised me most is that he said "Innovation often happens first outside of big listed businesses". His comment certainly made me think but I wasn't sure if it was valid - can you shed any light on this?

My dissertation is about social media's influence on the corporate environment. The research I have done so far clearly shows that the people in the corporate environment are more reluctant to implement social media initiatives, why is this though? Are they simply sitting back watching other organisations make the mistakes so they can learn from them? Or are the risks of implementing and maintaining a social media strategy too great in the corporate environment?

I would love to hear your thoughts on this. Also, I have created a short survey which is acting as a research tool for my dissertation; I would really appreciate it if you complete it and forward it on to your friends and colleagues. Here's the link: http://bit.ly/9T6r8h

I think it's a really interesting topic of discussion, I hope you can enlighten me with your knowledge and experience!