I had no idea it was available anywhere to just anyone, and without a backup driver in the driver seat. It still isn't to me in the UK, but really cool to see, it's a lot further along (especially in terms of regulation/being allowed) than I realised.
There is a backup driver, in an operations center, via data uplink. When the car is confused, it asks for human help. It's more of a system to help with decision making and perception than to drive the car by remote.
Is the backup driver expected to intervene in "urgent" situations ("What's this thing on the road in front of me? Should I stop?") or just in "confusing" situations ("I'm stuck behind a vehicle, should I drive around it?")?
See https://news.ycombinator.com/item?id=28290765