Actually Aramaic, I believe, is the liturgical language used by Catholics of the Chaldean rite. Latin, on the other hand is the official liturgical language used in the Roman rite and also the Ambrosian.
Well, your post sent me off on a whirlwind tour of the 5 Christian Communities or Rites. Along the way, I came across a site that provides a thorough, historical perspective on the origins of the christian church. You may find it interesting, too. Here is the link: