[antoniomika]

It definitely works! I haven't tried muting explicitly, but I've been able to control play/pause and volume well. This past weekend I tested out the development of actions on Google and the development of skills is more or less similar. The documentation still needs some work but overall the experience was fairly straightforward.

[dgacmu]

Confirming - I'm using it that way right now. Sometimes if you're doing something funky you have to explicitly specify the name of the chromecast. ("Pause the kitchen speakers"). But for the most part, it just works.