If your company is talking about incorporating social media, you'll probably be interested in this research by Burson-Marsteller and Proof Digital Media. (I stumbled upon this on the Fuel Lines blog.) It looked at Fortune 100 companies and found a little more than half are using Twitter. About 29% have a Facebook fan page.
The slideshow below breaks it down and gives some examples of how these top companies are effectively using Twitter and Fan Pages.