NPR and Edison recently released a state of the union report on the Smart Speaker space with responses from 1800+ respondents (note that 800 of the online respondents all owned a smart speaker). A couple of key takeaways:

16% or 39 million Americans 18+ Americans own a smart speaker
Amazon's Alexa is the most popular with 11% and Google Home is second with 4%
Time spent with the speaker is replacing AM/FM radio for 39%, smartphone for 34%, television for 30%, tablet and computer for 27% and 26% respectively and most notably print publications for 23%
51% using more in the months following the first month
Top tasks are playing music, answering a general question and obtaining the weather
On the commerce end, 31% report having added an item to cart, 29% researching an item, and 22% have reported reordering an item and ordering a new item

Bottom line: Smart speakers have been firmly planted in the homes of millions with surprising results in browse and purchase habits.