Not really that bothered if he leaves since he is not a regular starter for us anyway. But considering his age, contract lenght, being a Spain international & our lack of strikers at the moment, I see no reason to why we would let him go cheap. If we would sell him to Barca for anything less than £70m, it would be time to ask questions about which club Txiki has been working for when negotiating this transfer.
Personally I doubt he will leave this January. Cant see Barca being able to afford him, and its just noise to please the demanding fans. See some people saying they can just pay the fee over 5 years, it doesnt matter to City. It does matter, because if they dont pay like they should it will cause us problems when balancing the books in the future. And Barca are not exactly known for paying their transfers fees when they should, they owe money to half the clubs in Europe because of overdue payments at this point.
But if we could get Torres out and Joao Felix or Vlahovic in for the same money in January, I would happily do it.