http://www.techradar.com/news/amazon-echo-speakers-now-have-the-best-sonos-feature-multi-room-audio

If you thought the McGregor-v-Mayweather was going to be the best fight you’d see in 2017, you might be sorely disappointed: Sonos and Amazon are preparing for an all-out brawl in the connected speaker space. 

The latest barrage of blows happened this morning when Amazon added multi-room audio support to the Alexa app, allowing you to group Amazon Echo devices together – a move that effectively copies Sonos’ greatest strength.