Existing hearing aids have directional microphones, can distinguish between talking and background noise
Not very well - they can perform well enough to make speech intelligible (and it doesn't take much, human hearing is geared toward recognizing patterns) but the quality is fairly low. That's fine for hearing aids, because low-quality intelligibility is better than no intelligibility, but the technology is nowhere near ready for the quality that consumers with normal hearing would expect.
This might make a decent research project for the MIT Media Lab or Fraunhofer Institute, but it's an idea that's a long way from being ready for primetime.
Not very well - they can perform well enough to make speech intelligible (and it doesn't take much, human hearing is geared toward recognizing patterns) but the quality is fairly low. That's fine for hearing aids, because low-quality intelligibility is better than no intelligibility, but the technology is nowhere near ready for the quality that consumers with normal hearing would expect.
This might make a decent research project for the MIT Media Lab or Fraunhofer Institute, but it's an idea that's a long way from being ready for primetime.