It is a “whodathunkit” kind of thing, isn’t it? A web log, with its straightforward elegance, its honest and reciprocal dialogue, its inexpensiveness (though time is money), has become the next darling of marketing and public relations-a real time, two-way walkie-talkie, a bulletin board of instant feedback.

Don’t think so? It’s always good to keep an eye on the industry pace setters. When blue chip behemoths begin to recognize the power of the blog, those who were barely aware of its existence begin to sit up and take notice.

IBM, Microsoft, Yahoo, Google-not exactly small fries in the business world-all have/allow/encourage/regulate blogging from within their ranks.

Or maybe you should ask Dan Rather and CBS if blogs have any real influence on events and futures.

The blog has exploded. So much so that Merriam-Webster’s Dictionary awarded it “the word of the year” in 2004. In that year, the percentage of Internet users who had read blogs spiked sharply from 17% to 27%. In the US, that translates to 32 million adults.

Still in its infancy, blogging is easy to pick up and is surely being utilized to its corporate potential right? Not even close-eMarketer reported that just 4% of major US corporations have publicly accessible web logs.

And that, dear readers, is a huge waste of resources.

Just from a marketing standpoint, the demographic that blogs typically reach should be attractive enough. The highly coveted, proven-to-be-lucrative, unsettled in spending habits, frequently targeted 18-24 year-old age group is more than twice as likely to read blogs than the rest of the general population.

Talk about a golden opportunity to build a relationship with future consumers!

And that is what blogs can do so well-build relationships, the heart of marketing and PR. Better than broadcast, which is literally like fishing for an audience, a web log can target a precise and already interested user base, virtually free of charge.

“What’s fundamentally different about blogs is that you can be very successful if you find effective ways to get to the really precise audiences you want to reach,” said John Lee, vice president of marketing at Hostway. “It’s a way to reach the right people in ways you could not do before.”

IBM(pdf) recently began encouraging employee participation in the blogosphere and released goals and guidelines for employee bloggers. The company believes web logs to be a way of transforming an industrial icon that seems distantly squat upon an unreachable corporate mountain, into a “corporate citizen.” The goals expressed in IBM’s blogging policy are to learn and to contribute.

Web logs allow employees to learn from each other, from clients and from commentators. They also allow for two-way communication, a conversation in cyberspace that was hitherto mute, or at least, one sided.

“As an innovation-based company, we believe in the importance of open exchange and learning – between IBM and its clients, and among the many constituents of our emerging business and societal ecosystem. The rapidly growing phenomenon of blogging and online dialogue are emerging important arenas for that kind of engagement and learning,” as read in the guidelines.

The trick to it, though, is control of the information that is posted. These publications, even if altered later, can be accessible forever. It begs for review, asking, “who says what to whom and who approves it and what are the liabilities and if this thing blows up in our face who fixes it?”

Welcome to the frontier. It’s wild out here on the fringes.

Certainly caution is in order. People have already been fired for their blogs. Microsoft and Google both have pulled the trigger on their employees for blogging with poor foresight.

Michael Hanscom was fired from Microsoft for publishing pictures of Apple G5 computers being unloaded at the company docks.

Earlier this year, Google gave the proverbial pink slip to Mark Jen after he provided a bit too much infomation about life at the search engine company.

But control of sensitive company information is part of professional communication. Added to the overall corporate communication strategy, blogging can become an amazing tool.

In fact, I’d say it will become indispensable as it grows and as audiences become aware. Web logs will become the human face of the machine, the moderator of the conversation. And better, he who starts the conversation, usually gets the first and last word.

So if your company hasn’t set up a web log, I have to ask, “What are you waiting for?”