Sonos has now confirmed that Spotify and Alexa voice commands will work with their speakers on the 21st December. Currently, neither the new Sonos One (with built-in Alexa mics) or even a Sonos speaker paired together with an Amazon Echo Dot are able to start playing music from Spotify with voice.
Alexa is able to pause, skip tracks, and adjust volume for anything that’s playing on a connected Sonos system, so at the moment you can launch music from either the Sonos app or Spotify’s own app and then switch to voice commands for the absolute basics. But being able to tell Alexa (or the Sonos One) to play your Spotify playlists or a particular artist, album, or song on your nice Sonos gear from across the room will be far more convenient.
Currently Alexa on Sonos will play Amazon Music, Pandora, iHeartRadio, TuneIn Radio, and SiriusXM. Adding Spotify will really enhance reach in the market.