Google has just released an API for Google Maps! This is really good news for Web 2.0/mashup/remix hackers, not only because it presents an easy way to build location-based services using a Google Maps interface, but also because there was a strong concern among bloggers that Google might have legal trouble allowing external sites to re-use the map data. Fortunately, the problem's been solved; And even better, the API documentation makes it all sounds pretty easy. Way to go Google!
-- Update: A Yahoo! Maps API was released as well.