Basically what this would have done is create a unified British-French state. From what I've read, the French PM was a heavy supporter of it, and resigned when it fell through.
So I have a few questions to ask. How would the populace of France and GB respond to such a union, should it suceed? Would it result in more French refugees fleeing to Britain? How would such a union change the German occupation of France, if at all? And perhaps most importantly, should this unified British-French power survive post-WW2, how would it be viewed on the world stage? Would it be the third superpower of the Cold War?