I'm curious about what algorithms are being used. There's a lot of hands-on experience in music and audio engineering of eliminating noise and increasing perceived volume. I have a depressing feeling that audiology is off in a separate world, and the two disciplines aren't talking to each other as much as maybe they could be.
That's a good point about headphones, because the folds around the ears physically steer sound and add directional information that won't be picked up with a point microphone or reproduced with a pair of point headphone speakers.
You can fake the effect using either a plastic head with fake ears (it looks odd, but it works surprisingly well) or mathematically using something called a Head Related Transfer Function. (Great name...)
I suppose potentially you could improve noise filtering by increasing the effect of the HRTF. You'd get more directional hearing - which wouldn't always be useful, but could be an improvement in some situations.
(Just speculating...)
I'm far more seeing the privatised aspect of the field of audiology creeping in, with adverts all over the waiting room, and all reading material aimed at buying aids and accessories. I'd assume that technology development takes place within these companies in a fairly closed way.
I'd love to see one of those fake heads! Ad astra per aspera
And here's a commercial (if that's the word...) binaural mike system:
Dummy head recording gets rediscovered as a fun thing to do every ten years or so. Apparently Pearl Jam used one on a recent-ish album.