Early 08 STIs were recalled for a ECU reprogram. There is a TSB for that. Otherwise you're correct. They never fixed any other ECU problems to my knowledge.This sentence makes no sense. If you got boost cut and torque dropped off the car would feel like "night and day". Do you understand what torque is and how it affects your acceleration? Torque is a measurement of the force that is causing your wheels to rotate. It sounds to me like what you are all describing is some sort of boost cut and a lack of power to the wheels (loss of torque).
I think you all have the same terrible stock tune. If you get a stage one tune you'll probably be good to go. If you go to the dealership and it turns out to be something else please let us know but I doubt it.
Subaru is not likely to release an update for your ECU, the stock tune is not very good on any MY wrx and they haven't fixed it in the past.