From the Mapstraction site:
Users can switch maps as desired based on personal taste and quality of maps in their local area. Various tools built on top of Mapstraction allow users to easily integrate maps into their own sites, and configure them with different controls, styles, and provider.
I plan to discuss Mapstraction more over the next few posts. With Google’s recent change to their API Terms, many are switching from the Google Maps API and Mapstraction will undoubtably play a role in some users’ transition schemes.