Later this year, Granada TV are moving to the new Media City complex at Salford Quays in Manchester and building a new set there. Whether the potential listing of the old set is true or just ITV spin I do not know.
Granada used to do tours of Coronation Street. Maybe they just want a bit of publicity before building a new set and re-opening the old one to tourists.
It is not the original set, though. When I first worked at Granada, there was an older outdoor set which had not been built to normal proportions. It had been built slightly smaller than real life to save money on construction costs but, with careful camera angles, it looked perfect.
You only noticed it was slightly smaller than reality if, for example, you stood in the entrance door of the Rover’s Return pub… and you discovered you were slightly taller than you normally were.
The new set (the one English Heritage are allegedly thinking of listing) is full-scale.