Waymo has been giving rides in autonomous cars in Phoenix to invitees for almost two years now, but it said Thursday that it would open up the program to the general public. Which prompted Tesla CEO Elon Musk to chime in, for some reason.

Here are the pertinent details, :

Beginning today, October 8, we’re excited to open up our fully driverless offering to Waymo One riders. Members of the public service can now take friends and family along on their rides and share their experience with the world. We’ll start with those who are already a part of Waymo One and, over the next several weeks, welcome more people directly into the service through our app (available on Google Play and the App Store). In the near term, 100% of our rides will be fully driverless. We expect our new fully driverless service to be very popular, and we’re thankful to our riders for their patience as we ramp up availability to serve demand. Later this year, after we’ve finished adding in-vehicle barriers between the front row and the rear passenger cabin for in-vehicle hygiene and safety, we’ll also be re-introducing rides with a trained vehicle operator, which will add capacity and allow us to serve a larger geographical area.

Previously the Waymo-selected riders used the service under nondisclosure agreements, so it’ll be interesting to see what people self-report. Waymo claims the people under NDAs have said it is a “magical” experience.

This will all happen in a 50-square mile area that is geofenced, and only for the next several weeks, after which safety drivers will return and Waymo will double the size of the service area, .

But in this period of going exclusively driverless, “we will learn a lot about fully driverless service at scale, and that allows us additional clues on when we can open up the tap,” [Waymo CEO John Krafcik] said.

This is as good a reminder as any that if you take a ride with Waymo you are volunteering to be a guinea pig. But maybe that’s also part of the appeal!

Anyway, Waymo is very excited about all of this—a reference to Kitty Hawk is made in their press release—and it should be, being the consensus industry leaders in autonomous tech that it is. But Tesla CEO Elon Musk took a look at today’s news and shrugged, prompting the following response from Waymo:

Better was the shade in Waymo CEO John Krafcik’s response:

Krafcik one, Musk zero.