From google earth blog:
June 6, 2012
Google is unveiling the "Next Dimension of Google Maps" todayToday at noon EST / 9am PST, Google is hosting an event to show off the "Next Dimension of Google Maps". While we aren't sure exactly what they'll be unveiling, we have a few ideas.
In addition, the "next dimension" likely refers to additional 3D content. Will we begin to see textured 3D buildings in Google Maps? That might be possible, though part of the beauty of Google Maps is how lightweight and quick it is.
Perhaps they'll be incorporating Historical Imagery into Google Maps. It seems that it would be relatively easy to do that, since they already have the data for it, and "time" could be the next dimension they're referring to.
Paul van Dinther posted his thoughts on Google+ a few days ago. Considering the extensive work he does with Google Earth and the Google Earth Plug-in, he opinions are worth some weight. Granted, he doesn't yet know what they'll be unveiling either, but he thinks perhaps fully automated 3D buildings may be coming -- certainly a possibility after Google's recent sale of SketchUp.
In any case, we'll find out soon! Stay tuned and we'll post updated information as soon as it is announced.