Night Elves abandoned Arcane Magic while the Highborne kept using it. The Highborne were exiled from the rest of the Night Elves on Kalimdor. I'm guessing that the Night Elf Mages in this expansion are gonna be Highborne. If you run Dire Maul, you'll see a lot of Highborne Exiles there.
using arcane-magic is sentenced with death, ever since the great sundering.
it doesn't really make sence but oh well

tauren paladins don't make sence either... who cares as long as i have my undead hunters
I hope they implent a race change system..so I can change my race without changing to the alliance :/