What is a good map API that can display not just a static image, but the ability for the user to interact, zoom in and out. Additionally, what is a map API that can accept a street address and not a geo code?
update: Is it possible to get driving directions from an embedded map API? Such that the user can click onto a node and bring up a "where are you driving from?" prompt.
The google maps API would work well and you might also want to look into ESRI's web mappings APIs (JavaScript, Silverlight and Flex versions available).
Regarding the address, all web mapping APIs are going to make you geocode an address to get a point on the map. This is trivial to do. All of the APIs I've mentioned provide a function to do this and you just have to handle a result.
Although I'm a big fan of Google Maps, to be different, I'll suggest OpenStreetMap. I haven't used it in any projects, but it looks quite promising.
OpenStreetMap also has a geocoding function, similar to Google Maps.