A member of the Google Earth team writes in:

Here are a few database details you’ve not yet noticed…

• US Congress information has been updated to reflect the 110th Congress (Senators and Representatives) who took office on January 4th.
• Updated content from the GeoWeb layer data sources (example, more than double the number of Panoramio photos)
• Updates to other data layers (Volcanoes, ESA images, Tracks4Africa, etc.)
• Updates to GEC [Google Earth Community] content to capture latest posts there.
• …and as always, lots of subtle changes to refine both client at data.

it’s always good to have somebody looking over my shoulder…:-)