Google has updated the imagery for Google Earth, providing high definition views of many more locations, including:
UK images have been updated so that most of England is now in high resolution
New color mapping for Germany
Parts of Antarctica, Greenland, and Canada have been updated
High resolution updates for parts of Japan, Russia, New Zealand, Iran, Spain, Austria
More high resolution images for U.S. cities including Washington D.C., St. Paul Minnesota, and Houston Texas.