I have written extensivly on knowledge managment in the past. Two years ago I arrived at the sad conclusion that very few companies can actually enjoy knowledge managment. Well McKinsey & Company is definantly one. I had the pleasure of hosing David Chin in a Enterpise 2.0 conference in Janurany 15, 2007. His presnetaiton highlight the committment, and the value that McKinsey hopes to get from KM -- especially when it comes to new tools like the Wiki.
If you need the details please contact David_Chinn AT mckinsey.com
Note: I am publishing this on Feb 24, 2007; but it will move to the Jan 15, 2007 - close to the event.