The fact they are offering a retrofit at all says a lot about the Company. I can't recall the last time a car manufacturer offers upgrades direct of factory options to prior vehicles. If this is successful, perhaps there will be more in the future.
Actually all Tesla ever said was that it would put people on an interest list and based upon the level of interest, they would make an announcement "in a few weeks" about whether a retrofit will be offered and for how much. They may still decide not to do it.