(The following is pure speculation, so feel free to ignore it if you’re here for news)

It’s 2008, and Google Earth has evolved. It now comes with simple SketchUp tools in the free version, and many people are building virtual structures on Google’s Earth. How might this work, practically? Specifically, what happens when several different people want to build on the same spot?

Sources will be plentiful: Already today, Google provides a default layer for its buildings. You can also import structures via static KMZ files, such as those provided by ZNO and Digitally Distributed Environments. These files usually involve a single structure or collection of related structures, because file sizes for KML structures can grow large very quickly.

But there is no reason why 3D structures can’t be returned as part of a dynamic network link that polls your location, so that only the nearest structures are rendered from a much larger library, much as how Google’s building layer manages it now. And so I imagine that a third breed of content provider will emerge, serving up dynamic 3D content across the globe from a large library of available structures.

Who might these content providers be? There’d be an open source movement, of course, with user-contributed content systematically filling in gaps in its library. There’d be free content offered by commercial businesses, funded by virtual billboards and rooftop ads. There’d be pay services, offering premium works for those who want the highest fidelity models. There’d be content offered free by architecture firms as a way to ply their wares. Real Estate companies would release their beachfront condos onto Google Earth before building them, to generate buzz and sales. Other sources: City councils, hotels, artists making fantasy constructions, roadside franchises, architecture magazines…

Who decides which layer gets precedence in case of an overlap? Google? I don’t think so; I think it will be you, but it will require a control panel interface that lets you rank your 3D content. At the bottom might be Google Earth’s default layer, followed by the free layers, followed by the one or two premium ones you might subscribe to; at the top would be your own creations. But you order them as you wish, and you add only those you like.

Google might of course sell access to its base layer, or offer other layers as default options (for a fee, akin to browsers coming with pre-made bookmarks or Windows coming with pre-made desktop icons). In the end, however, each user’s Earth will be unique.

One further consideration: With OGLE able to copy 3D structures wholesale, it won’t be long before intellectual property battles come to Google Earth. Will there be pirated versions of paid content? Is re-using Washington’s virtual head from somebody’s version of Mount Rushmore fair use? Who owns a virtual 3D model of a famous living architect’s work? The maker of the model, the architect, the architect’s firm, or whoever paid for it to have it in their Google Earth?