Post by Skyfire
1. God no. The Mage forums are exactly like every other class forum, with the exception of about 5-10 posters: Lhivera and Irontygress, off the top of my head are very much about helping you improve your game as a Mage. And no, mages don't require penultimate skill to break 1700, but skill always helps. :) Get some good practice in on your way to 70, as you will be playing against people who didn't not pick up the class after the first 60 levels.
2. We don't flame here. We very much hope we aren't the main WoW forums. Um... I'd probably go Frost with you, for leveling as well as Arenas at 70. Easiest to learn: it's a lot of Frostbolting. :D
As for build choices, you should probably attempt to end up with 10/0/48
(plus 3) or 17/0/44
. In the first, I'm not quite sure where to put the last three, though I'd lean Frost Channeling. As for the second, Frostbite could probably be moved into Frost Channeling, Perma, or Ele. Precision, though I would go with Frostbite. The Arcane in both is primarily to: reduce aggro, reduce resists, get Clearcasting, and (for the second) get Imp CS, which is a good PvP talent. It would be a good idea to learn how to CS without the improvement, as the school-killer is oh so much more important than that silence.
Back to cookie cutter for you :P. Much as I love(d) elemental, it just doesn't work viably in PvP, and less viably than other builds. Clearcasting absolutely kills it.