This is an interesting development. Later this month, Google Maps will take over as the map provider for the OnStar Navigation service. The maps will be the same Google Maps we all know and love, but it will also include additional feature, like OnStar eNav, a feature of Turn-by-Turn Navigation.
OnStar and Google have reached an agreement that will let OnStar users search for and identify destinations using Google Maps and send those destinations to the Turn-by-Turn Navigation Service in their vehicles.
OnStar eNav, a feature of Turn-by-Turn Navigation, will become available through Google Maps at the end of this month. Drivers can access the destinations whenever they choose and get OnStar Turn-by-Turn directions to the destination from wherever they are.
Turn-by-Turn Navigation is the most widely available built-in navigation system in the automotive market today.
Model year 2006 GM vehicles and newer with turn-by-turn capabilites will see the new mapping features. Model year 2011 vehicles will see OnStar services as a standard feature for cars and trucks equipped with the OnStar capability. As of 2010, there are 35 vehicles across 6 brands that come with Onstar. You can see the full list here.
I think the OnStar/Google mashup will be a good thing for moving towards seamless integration. Given FroYo's new send to Android feature, you'll be able to send a map to your phone, then hopefully use your car's bluetooth to send the map to the on-board navigation. Or better yet, push the map right to your car before you even unlock the door.