To recognize the huge potential social networking offers for companies looking to improve knowledge sharing and collaboration among their employees, consider these two facts:

-- About half of company knowledge-management initiatives stagnate or fail.

-- There are about 131 million U.S. Facebook users between the ages of 18 and 64, and more than 500 million world-wide.

That's more than half a billion people using the same kinds of tools so many companies have struggled to put to productive use. In their private lives, users of Facebook, Twitter and other social media are completely at ease forming communities of shared interests and keeping everyone up-to-date with messages, pictures and documents. Now they are ready to put those same tools to work at the office -- to help everyone see who knows what, who needs what information, and how to coordinate their work.