John Udell wrote an excellent piece for InfoWorld pointing out a lot of the technology behind the rendering of maps in the Google Maps service. Udell points to an article by Joel Webber that really gets into the details of how a Google Maps page is constructed. There is lots of discussion of the intricacies of DHTML and XML for you web design geeks.
The details of Webber’s analysis are beyond my level of experience at the moment. I’m not looking to hack Google Maps or create a similar service, but I’d love to see documentation of how to call it and pass street addresses to it so I can generate maps and directions from my websites.