One topic I talk about in the call which I didn't cover in my previous post is where the Google street data comes from (they haven't said anything about this). To me it looks like a mixture of data they have captured from their StreetView cars, which seems to be good quality, and then probably TIGER data, which is much lower quality, where their cars haven't driven. Quite a few people have reported finding errors in street data that weren't there previously since the change. I found that Central City Parkway was missing from the map entirely, which is a pretty major highway that was completed in 2004. You can see this below, with OpenStreetMap on the left, and Google Maps on the right (screen shot using GeoFabrik's nice map compare tool):
I've reported the error to Google, so it will be interesting to see how quickly it gets fixed - and in general, how quickly they are able to fix up the apparently lower quality data in areas they haven't driven yet (though this assessment is not based on anything scientific).