This “vehicle-to-vehicle” communication and related technologies can be used to implement crash-warning systems, and lane departure alerts. According to the NHTSA’s Administrator:
Our research shows that these technologies could help prevent a majority of the collisions that typically occur in the real world, such as rear-end collisions, intersection crashes, or collisions while switching lanes.
Actual self-driving cars aren’t really on the NHTSA’s radar yet, but they promised to look at the technology as it develops.