Getting on the map is more than a metaphor this week. Today, Google unveiled "the next dimension of Google Maps" at an event where it demonstrated 3D mapping, called MapsGL, and the ability to use Google Maps offline. The 3D move seems designed to stake a claim to 3D mapping before Apple's expected announcement of its own 3D map app at its Worldwide Developer Conference next week.

At the event, Peter Birch, project manager of Google Earth, went through the evolution of dimension on Google Maps, from flattened to photorealistic. While Google Maps images had been cobbled together from multiple sources, MapsGL is powered by automated technology to extract 3D from aerial images that Google obtained from a fleet of planes it contracts with that fly exclusively for Google. This, combined with the release of MapsGL for Android and iOS in the next few weeks and the already over one billion users of Google Maps, considerably raises the bar for any maps announcement that might be forthcoming from Apple (though MapsGL was demonstrated on an iPad).

Apple's iOS wed Google Maps in 2007. In the years that followed, the two companies have squabbled over Maps, disagreeing about the look, data-collection habits, and discrepancies between the Android and iOS versions. Now that divorce seems imminent, the distance between Google and Apple is likely to only make mapping a more contested area—and one that others might take advantage of.

To get a bird's eye view of who's claiming what terrain in the 3D maps world, take a look at the story below.