Word from the official WoW forums is Magisters' Terrace (or MgT as we'll call it - thanks Ratshag) is too easy....or too hard...depending on who you ask.
We outgeared the place on normal so I can't really give an accurate assessment. (I hate when someone says "It's easy, L2P!" and you inspect them and they are wearing gear from BT.)
But my observation is it will be tough on normal for the people it was intended for (they said it is supposed to be on the level of Shadow Labyrinth and Shattered Halls).
Edit: The justification for the difficulty is the epic drop at the end.
Roll20 - First Game as DM
15 minutes ago