I have a code where its using AGS service as base layer
    map = new Map("map", {
          center: [-100.802650500000030000,36.300031299999990000], // long, lat
          zoom: 10,
          sliderStyle: "small"
        });
  currentbaselayer= new esri.layers.ArcGISTiledMapServiceLayer(baseUrl);
  map.addLayer(currentbaselayer);
I want to replace the currentbaselayer = "GOOGLE HYBRID LAYER" 
can some one get me an info on this?
TIA