The choice among Web 2.0, Web 3.0 and the Semantic Web is becoming something of a verbal Rorschach test, revealing whether one views the future of the Web as an evolution, revolution or transformation.

There are larger-than-life personalities behind each choice. Tim Berners-Lee returned with the Semantic Web, which as the name suggests, looks for meaning in the relationships among formerly discrete strands of Web data.

Publisher Tim O'Reilly's Web 2.0 was conceived as an interactive marketer's dream. It was originally used to describe the confluence of social networking and collaboration, user-generated content and folksonomies, and the rise of the mobile Internet and various nomadic networked devices.

John Markoff of The New York Times coined Web 3.0 to describe a third generation that puts a premium on using natural language, data mining and machine learning in search of an intelligent Web.

EarthWeb co-founder Nova Spivack amplified Markoff's Web 3.0, harmonizing it with the best bits from Berners-Lee's and O'Reilly's visions and adding what he calls the massively associative World Wide Database.

That isn't to say the three assent on all points, or that everybody agrees with them. The Internet runs hot with self-styled critics who find fault with each model and naming conventions that suggest the Web is developing in an incremental, linear process.

A trio of public servants brings helpful perspective to all of this. Dave Fletcher, director of Utah's Division of Information Technology Services -- and one of the longest serving and steadiest hands in the e-government movement -- is firmly in the corner of the nascent Semantic Web. These technologies hold the promise of addressing one of the most intractable problems of government by not only unearthing formerly disparate data from a federated environment, but making meaningful connections among them.

John Miri, director of special projects at the Texas Department of Information Resources, thinks that for most public leaders, the most important thing to understand about Web 2.0 is the "2," as in two-way communication or conversation. He said knowing how the technologies behind social networking, online collaboration and user- generated content work is less important than understanding that they are changing the relationship between governments and the people they serve.

Virginia Secretary of Technology Aneesh Chopra sees an immediate application of Web 2.0 in the creation of online communities around issues that matter to their members. To put it in the context of the public mission, consider such a community for the new generation of veterans in which they "answer each other's questions essentially eliminating the need for an 'expert' adviser to weigh in. They have the ability to self-police and find who has the best comments and how reliable they are. This notion of citizen self-help is a powerful one."

Chopra's application of Web 2.0 in service delivery reflects a major theme in the Center for Digital Government's most recent signature white paper called Simple.gov: It's Time to Change the Story. In it, co-author Rich Varn and I predict that "you will know that the era of complex, analog government is coming to a close when public institutions overcome the long practice of trying to bring or win the public back to government on its terms. You will know that we have turned the page toward simple, digital government when public entities focus on bringing government forward into communities where the public lives -- and do so on the public's terms."

If Web 2.0 is about knowing what citizen's know, want and value, and if the Semantic Web is about government knowing more about what it knows (by making otherwise hard-to-find connections), then the future holds incredible promise and the reasonable expectation of a few bumps along the way. Fletcher, Miri and Chopra would likely agree with what O'Reilly recently told BusinessWeek: "Web 2.0 is the messy way that the Semantic Web is actually happening."

Paul W. Taylor was the deputy CIO of Washington state prior to joining the Center for Digital Government as its chief strategy officer, and has worked in the public and private sectors, the media and Washington's Digital Government Applications Academy.