I mean in their data center. Also, I'd be more impressed if they actually got the self-driving cars out to the world. It's been 5 years now. Google has a problem executing, they're lulled by their one success.
If you live in the Bay Area you see the automated cars driving Google Employees to work all the time. I used to get an SMS any time somebody saw one (they are very distinctive) - but not as often, because people are starting to get more used to them. Though, they are still pretty cool to run across.
I'm impressed because people have been trying to nail this problem for decades. Try convincing people that a few million automated half-ton canisters of metal going 60 miles an hour are safe. An early success will win investors or make a nice press release, but developing a rigorous, safe product of that complexity and risk is a long slog. It's got to be so well understood it's boring - then it's ready for massive public use.