Despite criticism about Tesla's autopilot functionality, Musk claims autopilot technology is rapidly evolving. He believes it's already better than human driving, or will be within the coming months thanks to machine learning. Musk did mention though that eliminating the human completely is still not possible, as the cars need more hardware and software, more cameras, more radars, redundant electronics, and redundant power buses.
Jalopnik has a nice overview about the recent Tesla Model S update, besides the Summon featur it also included some features to enhance the safety of the autopilot feature:
As for auto-steer in the newly updated and not completely autonomous Model S, Tesla tweaked the feature to restrict speeds in residential areas or ones that lack a center dividing line.
Well, when Tesla says “restrict,” it’s not much of a restriction at all. In those cases, the car will limit its speed to just five miles over the actual speed limit in Autopilot. Of course, if you want to be a total hooligan there’s nothing stopping you from just driving it yourself like a nut.
When roads have faded dividing lines, an improvement on the Model S’ auto-steer will also help it to stay in its designated lane.
Other safety updates to the Autopilot system include a sytem that reduces the car speed as it approaches a bend in the road. That feature complements the aforementioned restriction that governs overall speed in specific, more dangerous situations.
In ~2 years, summon should work anywhere connected by land & not blocked by borders, eg you're in LA and the car is in NY— Elon Musk (@elonmusk) 10 januari 2016