https://arstechnica.com/gadgets/2019/01/google-assistant-flexes-on-alexa-announces-1-billion-strong-install-base/

The Consumer Electronics Show (CES) kicks off this week, and the show promises to be a voice command battleground. Before Google Assistant and Amazon Alexa start duking it out on the show floor, Google wants to let the world know just how many devices have access to the Google Assistant: a cool billion. Google says it expects to hit one billion Google Assistant devices by the end of the month—that's the total install base of devices that allow the user to issue voice commands to the Google Assistant.

Thanks to a report from The Verge, we also have really recent numbers for Alexa. Amazon just announced there are 100 million Alexa devices out there, so if we're treating all devices as equal, Google has ten times as many voice command devices in the wild than Amazon.