[_Adam]

You can now, multi room audio sync was added recently. I have two Echo's and I can say "play classical music [everywhere|office|living room]"

[mustacheemperor]

I don't really care about multi-room audio, I want to be able to play music through my hi-fi system by requesting it verbally, which works with the Google Home and a Chromecast Audio. There is literally no stereo image in these assistant-speakers, I wouldn't really use one for more than casual music listening (which the alexa is fine for, except for the limited library).

[cbhl]

But if I want to play a show on my Fire TV Stick, do I still need to use the Alexa microphone in the remote, or can I talk to my Echo?

[tdburn]

I believe you can now use your echo to control the fire tv

[bbgm]

That is correct. FireTVs ship with an echo dot bundle now for that reason.