Google has released aerial imagery for 16 more cities enabling more people to gaze upon their hometowns from a birds eye perspective. While Google has satellite imagery covering the entire planet, more detailed in some places than in others, this only provides a top down and rather high up view.With aerial imagery, you can get 45 degree view of the area, enabling you to much better make out the buildings and the layout of a less known part of town or a place you plan to visit.
Another benefit for having aerial imagery is that it enables enthusiast modelers to create 3D buildings for Google Maps and Earth with the Building Maker.
Here are the places where new imagery is available. In Europe: Caceres, Spain; Graz, Austria; Montreux, Switzerland; Zurich, Switzerland.
You can check out the full list of additions, including the places in the US, in Google's blog post
announcing the move.