Microsoft first revealed Cortana for Xbox One earlier this year at E3. In a promotional video demonstrating a new dashboard, Microsoft said at the time "Kinect required for Cortana speech recognition," but the company refused to comment on potential headset support. Microsoft appears to have figured out how to support Cortana on Xbox One headsets.
In an interview with Polygon, Mike Nichols, chief marketing officer for Xbox, has revealed you'll be able to use Cortana with a headset and microphone or by typing out a search. Microsoft is currently planning to roll out Cortana to Xbox One preview members by the end of the year, and to all Xbox One owners next year. "When we roll that out it will be a great experience for Kinect owners," says Nichols.
Microsoft now appears to be optimizing for Kinect voice use, rather than gestures to navigate the dashboard. "[Gestures] currently exist in the Xbox One experience, but we found so few people use it," Nichols says, so Microsoft has simply removed it in the new dashboard set to be released in November. "Now we're not designing for everyone who has it or everyone doesn't have it. We're designing for a good chunk who have it and use it and some new customers who now have decided to get an Xbox One who don't have a Kinect, at least not yet."