Just learned about WAZE  ( http://www.waze.com/ ) - the "Driver-Generated Live Maps and Real-Time Road Information" appliction for GPS enabled smartphones (just the Android right now)

It is not, as far as I can tell, an open source application, and there is very little info on the website. I guess one would need to sign up as a developer to find out what would be involved in getting street maps of NZ loaded...?  Still it is interesting to know what is likely to appear in the future.  The idea is a promising one!