When the folks at Google say their goal is to organize the world’s information, they aren’t just talking about bits spinning on Web servers or words printed in library books. To them, the world is information.

Witness the latest news to leak out of Google, by way of Silicon Valley Watcher: the company plans to create detailed three-dimensional models of the buildings of San Francisco by sending trucks equipped with laser range-finders and digital photo equipment down every street and alleyway. The data will presumably be added to Google Maps or Google Earth, the replacement for the satellite-imaging software Google acquired when it bought Keyhole last October. Google Earth, which is still in beta testing, can already display 3D shapes for buildings in selected cities, but they appear as crude gray boxes.

In January, Amazon’s A9 Yellow Pages added a cool feature called Block View, which shows a two-dimensional photo of any street address or business in 10 U.S. cities. But Google’s project is in a different category. Mapping buildings in 3D means that Google should be able to deploy the images in a number of ways: in local search results and Yellow-Page-type directories, sure, but also in fly-through city simulations, architectural concept drawings, video games, movies…the possibilities are enormous. (For one example of what can be done, check out the models Activision created for its Spider-Man 2 video game, in which players can swing freely around a photorealistic, 3D Manhattan.)

Starting with San Francisco is a no-brainer for Google. It’s close to their Mountain View headquarters, it’s bounded on three sides by water, and it has some of the world’s most dramatic architecture and topography. When Google publishes its data, tourists, house-hunters, developers, and others will have a new way to explore the City by the Bay before they visit.

In fact, I’d guess that in this age of digital imaging and mapping, San Francisco has become the world’s most thoroughly documented city. I’m reminded of The Illustrated Directory: Vol. 1, San Francisco, an 1894 guidebook shown to me recently by David Rumsey, a private collector of historical maps. This beautiful and extremely rare volume, full of artists’ engravings of each block of San Francisco’s business district, was unique for its time – and about 110 years ahead of A9 and Google. Without it, historians would know much less about the visual appearance of late-nineteenth-century San Francisco, much of which was destroyed in the catastrophic earthquake and fire of 1906. (To see the entire book, go to www.davidrumsey.com, open the “Insight Browser,” and do a search using the terms “illustrated San Francisco.”)

Which leads to an interesting thought: assuming that digital preservationists can figure out how to keep data intact across decades, our great-grandchildren in the year 2105 will be able to use information collected by Google, A9 and others to immerse themselves in virtual-reality renditions of today’s San Francisco–and, surely, Paris, Beijing, Cairo, New York…

It wasn’t so long ago that “digitization” meant converting printed pages to digital text. Now the process is being extended to our cities and even our bodies (for example, the digital Tom Hanks in The Polar Express). I once joked in print that I’d like to be able to Google my sock drawer for the missing half of my favorite argyles. That future may not be quite as ridiculous as I thought.