Polycom has the best conference telephone in the market which has similar capability. Plantronics headsets have long been using dual microphones to reduce near end noise to the far end. My 5 years old bluetooth earpiece does it pretty well as far as I can tell. It seems like this earSmart tech has something more than both Polycom and Plantronices have done. Any more information is welcomed.
If such a technology already exist which can reduce the environmental noise and send/receive clear voice then i am surprised that smartphone companies did not jump and put this feature. Its truly essential feature.
I think this technology would probably exists in many telephones used in conference rooms. Anyways it do not make any difference to the person in the noise environment, he will still needs to listen with the external surrounded noise.
One more step remains when incorporating lessons learned from the human hearing system into mobile phones. Cell phone offer very poor volume feedback to the user (which actually existed on conventional phones 50 years ago). This is a root cause of so many people shouting into their cell phones. When the speakers' voices are dead in the earphone, they naturally speak louder.