Winchester would not have remained the capital if any of the three had won in 1066. the best that Winchester could hope for was if Godwinson won it MIGHT remain the major royal residence otherwise its London with York a possible, receding in the distance, second if Hardrada won out.(Remember Canute used London as his capital)
If it had been a William/Hardrada split York stood a chance of being capital of the North but London would still be capital of Williams realm.
London it will be 99 times out of 100 (much as it pains me to admit it).
That 1 in 100 is if Wessex does not conquer the rest of England and even then London will be the beating economic heart of the country so the government will move there even if the Royals don't.