This won't be useful to me until Apple allows you to assign the default GPS app designation to a third-party app. Or unless they come up with a killer native turn-by-turn solution.
Apple needs to let Google fully implement Maps onto the iPhone as on Androids with its excellent turn by turn navigation. Only thing I still miss from Android. Well and my nice big screen. Just those two...oh and Flash. Just those things. But the only important one is turn by turn maps.
I think the Google maps in iOS is using the web service making it stripped and limited. At one point Google had a real app the way it has for Android and Blackberry, but the last thing Apple wants are iOS users being served well by Google. Maybe that'll change with the new leadership.