I cannot be certain but I imagine that the road system would have improved somewhat since 1945, that being more tarmacked roads and perhaps slightly more of them. Railways again I am not too sure about, I don't know if the French had an equivalent of a Dr Beeching so they might have kept more of their lines open. Buildings would be different in some places as many would have been rebuilt after the war and the population has grown a little since 1945 (I think the population of France was somewhere around 40 million in the 1940's and it now stands at 65 million, don't know about Normandy specifically though).
I would guess the modern day maps would not be too far off, the settlements and the location of many roads would be the same.