Google announced today the launch of a new tool that will dramatically change the virtual landscape of the company's Google Earth product. Cities in 3D is the latest of several free offerings from Google designed to encourage content sharing -- this time, people in small to medium-size cities across the nation and around the world will have the opportunity to swap more content.

Cities in 3D will allow localities to share with Google the data sets of any buildings within a city, and Google will render them into 3-D models.

"We're inviting local government to produce 3-D data that they can make available to Google users so we can integrate it into Google Earth and provide a rich, 3-D representation of their locality on Earth," said J.L. Needham, Google's manager of public-sector content partnerships. "We see this as a content partnership -- in this case a public-private content partnership in the sense this is the government making its data available to its citizens by way of Google Earth." 

As it stands now, generally the only cities in Google Earth that can be viewed in 3-D are those with large downtowns and business districts. For the first time, smaller suburban cities and even rural towns can contribute datasets, which will help to create a much broader virtual world than exists today. 

For Google, the partnership means those who navigate Google Earth will have a richer user experience. For participating cities, the possibilities are almost endless: From public safety to urban planning, cities of all sizes will be able to enhance everything from tourism to public input on new development. 

After evaluating the data a city uploads, Google will process the information using its 3D Warehouse technology. 

"3D Warehouse is a platform where any individual or organization can upload its 3-D models and have them viewable and editable by others, and when they meet a particular quality standard, they're added to a particular layer on Google Earth," Needham said. 

It will be up to cities how much, if any, of their content will be editable by users. In addition, city officials will determine the extent to which their city is rendered in 3-D. Depending on the type and quality of the data, city officials can expect to see 3-D versions of their municipalities in less than two months. 

"Typically it will take anywhere from four to six weeks," said Bruce Polderman, Google product manager for 3-D content. "What we do is we evaluate that data to ensure it meets our criteria, ensure the buildings aren't floating, that the data is accurate and that's its geo-referenced correctly on Earth. Certain data formats are far easier to process than are others. It really depends on what we receive."

Amherst, Mass., served as a test bed of sorts for Cities in 3D. The city's GIS office created structural models of Amherst's center using Google's free tool, SketchUp. Then the models were published to 3D Warehouse and added to Google Earth. Now anyone who wants to can edit the 3-D structures to make them as realistic as they desire. The 3-D models Amherst created have already factored into civic discussions about rezoning and economic development.