I’ve built a free, open source demo application, MapApp, to demonstrate how to use the Zillow neighborhood boundaries and integrate them with Google Maps, geolocation and geocoding.
MapApp is built using the Yii Framework and can be run on any MySQL/PHP-capable server. MapApp also leverages Google Maps API, HTML5 Geolocation helper from estebanav, eGeocoder and egMap (the latter two are Yii extensions).
How to Use Zillow Neighborhood Maps and HTML5 Geolocation