Steve a while back I saw a WatchDog type of program on tv, where the airlines were charging an arm and a leg because the ticket did not match exactly the passport name and details. Even though you have had confirmation that the airline will not charge you, I feel that in these circumstances the right hand does not always talk to the left and you might get to the various points of departure to find you get fleeced.
If I were you I would just let it go for now. Why make a problem 12 weeks before you go and risk having to pay through the nose for an extra ticket (worst case scenario) or any other fine because you just wanted to change Emma's name right now.
