There's a really (basic) reason why Open StreetMap has longer legs than ANY of the commercial company solutions (like Tom Tom, Nokia HERE (ex-NAVTEQ), GoogleMaps, etc).
The problem is solely one of maintenance.
How do these companies get their maps? They do so by driving over roads with equipment that collects GPS data (of varying degrees of accuracy... not important to talk about methods/accuracy for this particular point).
Think about that... when a company first launches (like Google Maps did a number of years ago), they can be "accurate" because they just drive around everywhere for the first time. That's relatively easy to track.
But then... changes happen. Roads get new construction, or there are new areas that are built up (with new roads or roads get new paths).
How does one keep track of all the changes that can happen anywhere in the world? One can't.
Well... a centralized company "can't." It is logistically improbable to keep a map up to date unless a company is planning on continuously driving every road because, frankly, it isn't notified about all the little changes that can happen anywhere; it takes a really long time to "drive every road."
It is no surprise that Google Maps has started to suffer from this. They were driving around and collecting their own data to make the maps and compete with the "other maps/navigation companies."
To that end, a concept of community supported map update (like OpenStreetMap) makes sense; I *know* when the street outside my house has changed. I can go someplace and make an update/submit information about a change when it is community based. In fact, I had to do this on several map company sites because my street was "new" for a new sub-division.
Now, with that said, there is one thing I'll say about Google Maps that might be a saving (?) grace: anyone using Google on their cell is "phoning home" a ton of information... including location (wonder how Google knows about traffic conditions when they don't have implanted sensors/cameras on the roads?). If they were to try and leverage that information, perhaps the map data can be kept up to date by (indirect) consensus based on drivers GPS intel. Of course, you won't get a lot of detail about non-popular travel points. And maybe that's the point... if they're dropping detail related to the less traveled/popular locations, that can fit with dropping their "go drive everywhere and measure it with a Google truck" plan.
I don't work for Google, so I can't speak directly for their strategy.
It just seems to fit a common problem with keeping any map up-to-date. How any company can keep an eye on relevant changes in a timely fashion?
Looks like they've given up on trying to "get it all" and are falling back on easy data from the Google hive mind. 8/