I know that method exists and is documented, but I don't know how to get an MapCanvasProjection object.
Look at http://qfox.nl/notes/116
var overlay = new google.maps.OverlayView();
overlay.draw = function() {};
overlay.setMap(map);
var point = overlay.getProjection().fromLatLngToDivPixel(latLng);
Ugly indeed. Much easier in v2 - another flaw of google api v3!