By Ken Makovsky

We're all aware of the enormous growth in corporate involvement in the social media, but Fortune 100 CEOs, surprisingly, are mostly absent from the great global conversation.

While some Fortune 100 CEOs contribute to other blogs, not one had his or her own blog, according to a study conducted by ÜBERCEO.com. Eighty-two percent did not have a personal Facebook page. Only 13 had profiles on LinkedIn. Only two had Twitter accounts. Of those F100 CEOs who had a profile on Wikipedia, nearly a third featured limited or outdated information (such as incorrect titles).

What accounts for this CEO "no show" policy? Possibly lack of time, doubts about value and concerns about legal constraints.

If you look at the top executives who do blog, you find a very heterogeneous group: hotel magnate Bill Marriott, John Mackey of Whole Foods; GM's Bob Lutz; craigslist founder Craig Newmark and Jonathan Schwartz of Sun Microsystems, to name just a few.

They're not all geeks … and they're certainly not all kids. Seventy-seven-year-old Bill Marriott created his blog because "I know this is where the action is if you want to talk to your customers directly." In an interview last year with MSNBC, Marriott said his blog also generated $4 million in bookings.

Fortune 100 CEOs should realize that participation in the social media puts a human face on a corporation. It helps build relationships, credibility and trust, among a whole host of benefits: enabling you to learn more about your constituencies and their needs, promote products and policies, address important issues and defend the company against its critics.

Five years ago, author, blogger and marketing pundit Seth Godin wrote "Beware the CEO blog." He said, "Here's the problem. Blogs work when they are based on: candor, urgency, timeliness, pithiness and controversy … Does this sound like a CEO to you?"

I say, "It sure does. Absolutely. Just not every CEO."

CEOs heading consumer product or technology companies or professional services firms with intellectual capital they can leverage are in the best position to reap the rewards of the social media. It may be more challenging for executives of companies in heavily regulated industries (like pharmaceuticals), corporations going through difficult times, if there are legitimate questions to which you feel you cannot give an honest answer or when your lawyers are saying, "Keep quiet." It's important to remember, however, that while there will always be questions that you may choose not to answer, you can be candid about that fact, within the confines of disclosure requirements.

That doesn't diminish the fact that blogging represents a CEO's best chance to reach out to and connect with stakeholders. How can anyone afford to walk away from that? Not to take full advantage of this important new communications asset is to put yourself — and your company — at a distinct competitive disadvantage. Don't make the same kind of mistake that Western Union made over a century ago.

Alexander Graham Bell wanted to make universal telephone service a reality quickly, so in 1876 he offered his patent outright to Western Union for $100,000. William Orton, the president of Western Union, turned Bell down flat, calling the telephone a "toy" with "no commercial possibilities." Dead wrong. Two years later, Orton said that if he could acquire the patent for $25 million, he would consider it a bargain. Too late! The train had left the station.

Don't let the future pass you by. Don't leave it to others. Don't walk away from the social media.