in #GMAP non vedo google.maps.LatLngBounds(); Molti esempi sul web lo utilizzano.
Esempio :
http://stackoverflow.com/questions/1556921/google-map-api-v3-set-bounds-and-center
Yes, simply declare your new bounds object.
var bounds = new google.maps.LatLngBounds();
Then for each marker, extend your bounds object:
bounds.extend(myLatLng);
map.fitBounds(bounds);
API: google.maps.LatLngBounds