Response to both you and joosters: I think you're being too strict here. Who knows what the threshold is? Maybe it works 100% of the time on highways. Maybe has problems only when there are no lines on the street? It's not a completely unsupervised technology and is not advertised as such. You can't even legally treat it as such - you have to be prepared to take over at any point.

Compare it to the regular cruise control, already present in production for years. Would you say cruise control is not ready for production or release on public roads? It's a tiny subset of what Tesla's update does. (and it doesn't even tell you when you need to take over)