Very interesting. I have to admit I am a bit doubtful. Part of me wonders if it is more of a nurture sort of thing where
the benefit the child is really getting is the type of parents who would buy the product. If you are willing to spend the money I would believe that you would also be more apt to provide interactions after birth that would help the very things mentioned in the demo.
I will be interested in sharing this link with my DH this evening when I see him online to see what he says (he is a music education major). I do know that he has scoffed at putting headphones on the stomach to play music for the baby just because of the volume (i.e. it is fine to play music just no need to use headphones on the belly). My guess is that he may scoff at this as well.

I will be sure to share his response.
All that being said I do not think that it would HURT to use. I just don't know how much it would truly help. KWIM?