Getting to know the new Mass
One might as well start with the "ordinary"--the parts that generally don't change, including the people's parts and the first four eucharistic prayers.
The first big change: "And with your spirit' as opposed to the "And also with you." Here's Father Rick Hilgartner of the USCCB Divine Worship Committee on the difference: "The current response, 'And also with you, was 'not meant as "you too" or something like "back at you," [It is] an invocation to the priest as he celebrates the Mass, a reminder that he is not acting on his own, but in the person of Christ" -- a distinction that the new language will highlight."
Not sure I'm buying this--why would the priest need to be reminded of such a thing? Is that why he said, "The Lord be with you" in the first place? So that he could be reminded that he's acting in the person of Christ? This unnecessarily clericalizes and complicates what is, after all, a simple greeting. Better to just say that it is a more direct translation of the Latin--which it is--though I still think "and also with you" makes more sense in English and more accurately conveys the idea.
Folks will also notice in the new translation of the Confiteor the repetition of "through my fault, through my fault, through my most grievous fault." Be sure and strike your breast as you say it. You'll also want to practice "consubstantial," which doesn't quite roll of the tongue as well as "one in being."
There are many other changes, some that are important but will go unnoticed, but one that I think is incredibly unfortunate is buried in Eucharistic Prayer II--the shortest and thus most commonly used.
In the new translation, after the memorial acclamation (Christ has died... Oops, that one is no longer included), we thank God because he has "held us worthy to be in your presence and minister to you." The old translation, in which we were counted among those "worthy to STAND in your presence and serve you" was the far more accurate translation of "omnes circumstantes," literally "those who stand around."
That expression truly reflects the ancient practice of the church (and begs the question of why everyone but the presider is kneeling at that point): an assembly gathered around the table of the Lord, granted the dignity to stand in the presence of God--not just "be." One is active, the other passive.
No big deal? Not if you think the liturgy effects what it signifies.