The LEAF's GPS/navigation system is NOT as good as others. It is deficient on a couple of major details, and these are NISSAN'S fault, not Navteq.
I took delivery of my LEAF last February 17 in Petaluma and needed to drive 86 miles from there to our home in W. Sacramento. Of course, I knew the way back, but tried to set my home address into the LEAF navi....NO GO ! None of my nearby streets were even IN the database of the LEAF. I got home and soon called Nissan and then Navteq to check out the out-of-date status of the LEAF GPS software. Navteq was quite clear on the point; they have sent Nissan updated details, but Nissan is about TWO YEARS BEHIND in their integration of Navteq updates to the final versions of software actually installed in Nissan cars.
I would further note, that our 2011 Chevy Volt does have ALL THESE STREETS in that GPS database; this development is at least FIVE YEARS populated, so Nissan is simply derelict in their attention to currency in their GPS software.
The second issue with the LEAF traffic warnings is that the system only works IF there is a route activated. There are no "proactive warnings" of traffic issues that simply arrive driving on a given highway (if you do not have that road as part of your active directional routing). On the Chevy Volt, the traffic warnings arrive for a given road, even without a specific route active--a MUCH better system.
So, clearly NISSAN simply has a THIRD RATE at best navigation/GPS system. Almost any portable unit, with included lifetime map updates, would be at least 100 times BETTER than what is installed in any of the Nissan vehicle line.