Comment: Re:Why would it need studies? (Score 2) 345
I use Waze for most of my navigation now, which also uses an open mapping back-end that's user editable. Winter roads are one of the features I've requested that it doesn't understand yet -- telling me to take a shortcut through a back road that's not open in January for example. Of course, as soon as I avoid it, it re-routes me properly.
One of the things I love about Waze is that it tracks your actual routes you take, and saves them on the routing server to help it make better decisions in the future.