The news that a third center-line road data provider is starting up is very interesting. In an interview with Directions they are relatively closed-lipped about why they think they can compete with the big boys, but a good guess can be had by looking at their earlier news releases. This not a road mapping company, this is a computer vision company. Presumably the liberal application of computer vision allows them to combine their GPS and intertial data with road sign readings to build out full navigation-restricted data without a heavy manual data post-processing step.
That still leaves the tricky aspect of actually driving their cars down every street in the country, and I wonder what mapping source they used to ensure they weren't missing any. The mathematics of driving every road in the country are also daunting: 4 million miles of roads in the USA, at an average speed of 20 miles per hour, for 8 hours a day, implies 25,000 days of driving! Or $2M using $10/hour drivers, plus the capital cost (at least $5M) of the 70+ vehicles needed to do the thing in about a year.
On the other hand, given that Nokia just paid $8B for NavTeq, the cost of entry into this marketplace is incredibly low — $20M maybe? I think I'm in the wrong business, time to hit the road!