You'll have access to Alexa's skills from the get-go, of course, but the big deal is that you can control playback entirely through voice if you like. You can tell the One to play music on specific Sonos speakers or throughout your entire home, for instance. And if you prefer to use apps, newly-added support for direct control and (in 2018) Apple's AirPlay 2 lets you skip Sonos' own controller software in favor of the likes of Audible, iHeartRadio or Tidal.
The speaker will cost $199/£199 when it ships on October 24th, which is decidedly pricier than your typical smart speaker, but on par with the One's voiceless precursor. Sonos is clearly betting that its reputation for good sound and its experience with whole-home audio will justify a premium. The catch, of course, is that Amazon, Apple and Google aren't standing still. They're all introducing (or expected to introduce) speakers that include voice assistants and should sound pleasing to your ears, possibly with higher quality than the Sonos One. It remains to be seen whether or not Sonos' name, audio technology experience and multi-assistant support will be enough to win people over.