Want cache google geocodes

I want return latitude and longitude geocodes from Google Maps api from an address string and cache these in a MySql table, co-ords will be used for loading a map at the location of the address. There are examples on the net for loading a Google map using an address, but this is without caching:

var map = new GMap2(document.getElementById("map"));
var geocoder = new GClientGeocoder();

function showAddress(address) {
  geocoder.getLatLng(
    address,
    function(point) {
      if (!point) {
        alert(address + " not found");
      } else {
        map.setCenter(point, 13);
        var marker = new GMarker(point);
        map.addOverlay(marker);
        marker.openInfoWindowHtml(address);
      }
    }
  );
}

I've also seen where a request can be sent with a url server side and it returns xml. Maybe that would work best for me using php, but I would have to parse the xml. All I want is 2 values, latitude and longitude so I can store these in a database table which would act as a cache. I would retrieve these values from the database for the same search to save time and number of calls to the Google server.

What format does the 'point' returned from getLatLng take? Can that be saved as is?

Any ideas please?