The policy covers all Superchargers, and any car (new or used) bought from December 15th onward. There may be exceptions to the policy for the sake of "specific local circumstances."

This isn't to say that Tesla frowns on commercial uses of its cars. A spokesperson told The Verge that it does "encourage" business use and will cooperate with drivers to find alternative charging locations. With that said, the move is bound to leave some companies scrambling. In many cases, they're using Superchargers for the same reason you would -- to extend their effective range beyond what they can get with slow conventional chargers. If a ridesharing driver has to take several hours to top up their new Model S instead of an hour or less, they may have to scale back their operations. Simply put, this could put a chill on certain commercial uses unless there's either a large-enough Supercharger network or third parties offer a viable alternative.