> Every city they hope to deploy in has differing signage, differing driving habits, and many funky intersections and road anomalies that need specific attention.

The very fact that those things do need specific attention tells me they don't have true autonomy yet; they just have a way to fake it using detailed maps of known areas.

I don't see how an autonomous vehicle can handle all the corner cases of real-world driving (construction zones, etc.) until it can also work reliably using only available sensor data, so that detailed mapping is no longer necessary.