It seems Tesla has given thought to front impact collisions.
However the car would provide two rear-mounted seats, for children, facing backward.
So the question comes how the car would handle a rear collision.
This is already being discussed in another thread, but there is not definitive answer yet:http://www.teslamotors.com/forum/forums/questions-about-rear-facing-seats
Kids (old enough to speak) would be a safety feature: screams of "Goose it!" should provide enough warning to get out of the way.