The California DMV's required autonomous vehicle disengagement reports are now online. A disengagement is when the human driver had to take over. These provide one of the few neutral assessments of how autonomous vehicle development is progressing.

- Google/Alphabet/Waymo: disengagements per mile down 75% this year over last year. 124 disengagements over 600,000 miles driven. Zero on interstates and freeways.

- Cruise/GM: 9768 miles, 231 disengagements. (Dec 2015 to Nov 2016).

- Tesla: 185 disengagements over 550 miles (not thousands) driven. Almost all the driving was in one month. Most driving was on suburban roads.

- BMW: 638 miles, 1 disengagement, on a freeway, blamed on poor lane markings.

There are other reports (Delphi, VW, Ford, etc.) but the number of miles driven isn't large and the number of disconnects is high, so they're still in the early stages of R&D. Honda is testing on a test track in Contra Costa County, probably the old Naval Weapons Station. Uber didn't file; they refuse to test in California because they'd have to report like everybody else.

So that's the real state of autonomous driving right now. Google is nearing production level quality, and is probably ready for freeway driving. Cruise is starting to log the miles, but is doing three orders of magnitude worse on disconnects than Google. Tesla is doing even worse. Everybody else is just getting started.