Student of the Mind

Increasing you total spirit by 4/7/10% is very nice, especially when coupled with Potent Spirit. More mana regen and spell crit? Yes, please.

Netherwind Presence

At max rank, this spell gives an array of Mage spells a 5% chance to make the next spell in that same selection instant. The spells covered by this effect include Arcane Missiles, Arcane Barrage, Arcane Blast, Fireball, Frostbolt, and Frostfire Bolt. This seems quite weak to me, especially coming as it does so deep in the tree.

What this means, in essence, is that every 20 Fireballs (or pick your nuke of choice) you throw, on average one will be instant cast. The proc could be more or less often, of course. Since Arcane Missiles and Arcane Barrage (we'll get to this little spell in a moment) are already instant cast spells, the instant effect can only apply to Fireball, Frostbolt, Arcane Blast, or Frostfire Bolt. If you're using Fireball or Frostbolt as your primary nukes, their cast time is likely already shortened by talents. If Arcane Blast is part of your rotation, you're likely already using the lowered cast-time debuff to your advantage. Frostfire Bolt appears to be the best option to use this proc on (assuming it's going to end up as powerful as it could be), but that's only if you notice that the effect has procced, and have the presence of mind to switch out of your normal rotation to trigger the spell. I'm sorry, but this spell may be one I skip over. It will definitely provide a small DPS boost over time, but perhaps not enough to be worth 5 talent points this deep in the tree.

Arcane Barrage

Alright, now we're talking. This spell has the potential to be fantastic, to completely change the way Arcane Mages play in PvP, and to almost single-handedly make the Arcane tree a legitimate spec choice that can stand on its own. I couldn't be more excited about this spell. It isn't physically possible. As a Mage who already specs deep Arcane despite my better judgment, the thought of getting this spell makes me very, very happy.

What the spell does, essentially, is provide us with an instant cast nuke with a very short cooldown (3 seconds). At max rank, it does damage comparable to a max-rank Fireball, for slightly less mana. What it will do is nothing short of revolutionary. This spell will allow Arcane Mages to provide high DPS while moving. I can't italicize that enough, frankly. Mobile damage. Say it aloud. Feel how it just rolls off the tongue. Arcane Mages will be able to hurt things consistently without having to stand still. I'm...I'm giddy.

There are still some questions concerning how much spell damage will apply to this spell. Reports from the Alpha put the spell damage coefficient as high as 85%. If that or a similar number hold true, what an astounding spell this could turn out to be. Bring on the nerfs!

All told, I have to say I'm fairly excited about the changes in store for the Arcane tree. As far as game-changing mechanics go, I'm afraid these alterations and new talents are as close as we're going to get, based on the information we have so far. The new Fire and Frost trees aren't nearly as encouraging. We'll get to those next week and the week after. Hopefully by then we'll have a bit more info, as Mages get into the Beta and start monkeying around with this stuff for real. Bring us some good news, you brave pioneer Mages.