D. Mark Hornung is attending this week's Web 2.0 Expo because he doesn't want to get hit by a tsunami.

A senior vice president at employment marketer Bernard Hodes Group, Hornung sees a tidal wave of blogs, wikis, social networks, virtual worlds, and other Web 2.0 applications approaching his industry. Along the way, these technologies are re-shaping employment marketing in fundamental ways that are more disruptive than the shift from print to online media, he said.

[ See related story on IBM's new server aimed specifically for companies running heavily trafficked Web 2.0 sites. ]

Prior to the Web 2.0 revolution of online communities and user-generated content, employers could still control their brand and their corporate message via their sites, online ads, and e-mail communications. Not anymore, according to Hornung, whose company helps clients promote their employment opportunities.

"Now you have the universe of prospective employees talking and connecting with each other, and that creates a whole new dynamic because now the employer doesn't control the message," Hornung said. "It's much more difficult to maintain a consistent brand image because you have people defiling it on the one hand and overly building it on the other. It's a fundamental shift."

"The message I'm taking to my clients is that you can no longer control the message, you can only influence it," he added.

Hornung will be one of about 8,500 attendees at the San Francisco event, which is geared at business and IT managers, senior executives, developers, marketers and entrepreneurs. Like him, many attendees will be interested in learning how Web 2.0 technologies are infiltrating workplaces.

Indeed, how to take advantage of Web 2.0 has become an increasingly loud and common conversation within companies. A recent Forrester Research survey found that Web 2.0 adoption is a priority at 56 percent of North American and European enterprises this year.

"It's safe to say that at just about any enterprise, somebody is thinking about Web 2.0 tools. It may not be the CIO, CEO or CMO, but someone is looking at these tools and to see if they can be used to solve long-standing business problems, and in many cases they can," said Oliver Young, a Forrester analyst.

While the opportunity that Web 2.0 offers for improved communication and collaboration with employees, partners and customers is clear in general, each organization must figure out its approach to choosing and implementing these tools, Young said. "The biggest question is: How do we use them properly?"

Young recommends that companies identify the business problem they expect to address and then determine the desired changes. Once that's done, companies must draft a strategy for triggering the change. Only then should decision makers begin considering what Web 2.0 technology to employ.

"That sounds like a no-brainer but so many companies start with technology and say: 'Well, we're going to bring in a wiki and then we'll figure out what we're going to use it for.' Doing it that way is a sure-fire recipe for disaster," Young said.

Another good idea is to start small by identifying a specific problem involving a discreet set of users. This lets the company test the system and reduce its investment risk, he said. "That makes it much easier to experiment and to iterate to find right formula for your company."

After all, Web 2.0 wares lend themselves to this type of test, because they are generally very inexpensive when compared with conventional enterprise software. A Forrester study released this week found that globally enterprises will spend only $4.6 billion by 2013 in Web 2.0 products, a small fraction of the overall software market. "While Web 2.0's impact will be very high, and make the enterprise fundamentally different technologically, the money associated with enterprise Web 2.0 spending is going to be relatively small," Young said.