I hardly think it's missing a trick to not offer an exchange. The Pro is not a 'replacement' for the RT, nor an 'upgrade' - rather a separate model. It's a little like a car company offering owners of the petrol model of one of their cars a trade-in when the diesel variant was released. (Please, no arguing over whether Petrol or Diesel is best!!). Think of the message it would send to offer an exchange for Surface RT owners - it would be an admission that the Surface RT (and by extension Windows RT) had failed, and would likely kill the product line!