Learning language is an interesting process that has seen study, but not much serious lab study. In this particular study, a scientist from MIT set up a series of cameras in each and every room of his house in order to study his child learning language. He did it for the first 90,000 hours of his child's life. According to my calculations, this comes out to roughly the first 18 months - nonstop video/audio recording of his child. While it may seem strange, it has been incredibly interesting. It revealed that infants in fact shape the way that their caregivers teach them to speak. Of course, others things were learned, but that was among the most interesting to me. All in all, this was an interesting study that absolutely deserves massive amounts of attention.
The only flaw I can see in this study is replicability. While it is completely possible to replicate this study, there are very few people that would be willing to allow cameras in their household. But, it was mentioned that they have been working on recording devices that are strictly audio, which is slightly less intrusive. But still, it seems unlikely that people would be open to constant recording within their household in every room that a group of colleagues will surely be intently studying.