As I found out, the navigator.geolocation object references the Safari
Geolocation API, not the Geolocation() phonegap function....so my
changes to the Phonegap Geolocation APIs weren't being picked up
because it is the Safari geolocation APIs being invoked at run-time.
A negative side effect is that the Safari API isn't nearly as
responsive or accurate as the iPhone native APIs (I think the Safari
geolocation stuff uses tower triangulation + Wifi location databases
but doesn't make use of GPS signals). I don't think this was intended
because the purpose of Phonegap is to leverage native APIs?