I noticed a field in the options to enter in a Google Maps API.
I signed up for one, and entered it in.

How does this work? Does it read my City, State info on individual photos? Where does it display?

You have to have latitude/longitude data in your images. (Picasa can do this.) Then you need to sign up for a api key and put that into your options.

Once done, when there is gps data in an image, a map of the location will be displayed.