This is another article from the New York Times about a study published today in Nature where researchers reported that the earliest behavioral sign that a child is likely to develop autism is when and how long a baby looks at other people's eyes.
The study found out that babies between 2 and 6 months of age who began spending less time looking at people's eyes paid less and less attention to eyes as they grew older and later on were diagnosed with having autism. On the other hand, babies who did not develop autism looked increasingly at people's eyes until about 9 months old, and kept their attention to eyes fairly constant into toddlerhood. The researchers used an eye-tracking system to figure out the babies' attention to people's eyes.
I think that this research is a major, major find for not only the science community, but for everyone, especially expecting parents.