In reply to Luke Pettway.

Luke - I did something very similar, integrated it to a site that was writing to a google map using PHP & Javascript, (600 + posts with co-ordinates, different categories etc...)

Recoded the map, using AJAX to get the JSON feeds from the API, and write directly to the map. Huge increase in speed. And flexibility. I can pull any of the custom fields, I have even pop-up booking widgets triggering from buttons in the resulting Google Map Infowindows.

When you get your head around it, its a fantastic resource. Awesome.