[smackfu]

Don't you need to buy the $4250 "Tech Package With Autopilot" to get this feature? It seems like that includes the various sensors for lane keeping and automatic cruise control. Or maybe every car includes the sensors, and you are just paying for the software?

[mikeash]

That last bit is precisely how it is. The hardware is there on all cars sold after mid-September 2014. The software features are divided semi-arbitrarily into "convenience" and "safety" features. All cars get "safety" features, but you have to pay extra for the tech package to get "convenience" features.