The ability to understand you involves understanding language. You have to understand the world to understand language. Google built a 70 node knowledge graph that drives their understanding of the world which enabled them to create a intelligent device. Or something that is more revolutionary versus Echo is more evolutionary.

I have both and purchased the Echo when first launched. The Google Home amazes me every day.

So with Home you say play Madonna song Sean Penn movie and live to tell starts playing.

Echo has a command of "goes like this". Never used it. But everyday Google figures out something.

Our understanding of the world allow us to talk in a condensed form as humans can infer a lot.

Google is doing the same so more and more I talk to Google Home in condensed format.

It is so early with all of this but Google has a incredible foundation. The future is going to be incredible.