He explained that they’re focusing on semi-controlled areas and that the driverless vehicles will serve a number of different purposes, both public and private.

I've seen a video of the snail that is the Greenwich autonomous vehicle (AV) a while back. The video made the point that the development of autonomous cars is strikingly similar to that of the very first cars with internal combustion engines. Compare these two:

The most draconic restrictions and speed limits were imposed by the 1865 act (the Red Flag Act) which required all road locomotives, which included automobiles, to travel at a maximum of 4 mph (6.4 km/h) in the country and 2 mph (3.2 km/h) in the city - as well as requiring a man carrying a red flag to walk in front of road vehicles hauling multiple wagons

I think it's a great parallel development. On the one hand of the speed spectrum, you have Tesla and Mercedes and Audi working on automating highway driving. On the other end you have companies like Google, Meridian and BMW to some degree putting a lot of effort in handling low-speed environments.

While they're diametrically opposed strategies (low- to high-speed vs high- to low-speed), I think they are both developed because they can be controlled the easiest. Highways can be simplified because it is an environment that's regulated and is fairly simple to explain to a robot. Pedestrian / busy zones can be controlled with speed. The slower the vehicle goes, the more time it has to figure out if you're a human or a tree.