Other than the leaked photos from last year I don't think there's been any new details. But they're clearly working on a headset; those photos are way too detailed and unique to be faked.
Any sense of what might be going on? A reference design for other manufacturers maybe? Judging by the small iterations between the latest developer versions of the Knuckles controllers you'd have to expect those to be released fairly soon. Seems like putting out a headset along with the controllers would make sense.
https://www.roadtovr.com/report-new-valve-vr-headset-appears...