The latest enhancement to the Google Maps API is Map Styling.
Map Styling allows developers to modify the look of the base map tiles, both in terms of what features are shown, and the colour scheme. This means that developers can change the look of their maps to suit the colour-schemes of their websites.
You can see some example styled maps on this demo page.
You can also use the Styled Map wizard to experiment with different styles, and generate the Styled Map definitions to use in your Maps API application.
The Mood of our Cities Now
NBC Local Media have used the new Styled Maps feature to show the most emotional stories of the day.
The map animates through news stories and displays the location of the story with the color correlating to how the majority of users felt about that story.
Via: Google Geo Developers Blog