I note no one has commented on what google’s motivation is for doing this…
Less time driving, more time on your phone/laptop/device(s) being bombarded with Google’s advertising. At the end of the day Google is an advertising company – it creates devices so it can target you with dedicated advertising.
You’ll get in your (driverless) car… car asks “where do you want to go” (search engine), owner: “To a italian restaurant” (search query), car offers several in the area (search results) – like ‘Pay per click’ Google will be paid for offering adverts etc.
Google will also be tracking your driving, where you’re going etc, and tailor the car to the user providing suggestions on where to go, what to do.
Regardless of their motivation though, what Google are doing is inspiring.