I know another difference (and some may see this as a small thing) and that is in the Credo, which itself is a word that means “I believe”. In our Mass we say “We Believe”. The correct translation would be “I believe”. There are many other places where the translation is not completely accurate although it is “close”.
My pastor has told me that the original English translation was hurried, and in his opinion, the result was a bit clumsy. The new, and more correct translation will not be a product of speed, for sure, and if not elegant, will at least be accurate. Elegance, of course, would be a plus, in keeping with the solemn nature of the Mass.
However, some may resist any change to the status quo, even if it is to change “slightly inaccurate” to “accurate”, because of the disruption that change represents. I hope that is not so. If there is any delay, I suspect it could be related to that, but I don’t actually know. It just seems likely to me.