What is the best dps spec for a mage lvl 35 in the most up to date patch? At lvl 50? At 85? And what are the primary stats wanted on armor? Stamina, intel, spirit, etc..

Spec pre 85 doesn't matter. At 85 Arcane has the most dps while not being very mana efficient. Fire remains competitive and is pretty mana efficient. The main stat you want is Intel.

Don't worry about dealing max dps pre 85. While you're leveling, you should be focusing on mana efficiency than dps. Which if I remember correctly is the frost tree, as it's spells are much more mana efficient and grants you a lot more survivability which is crucial as you are questing and leveling.

As Chuck said, at 85 the max dps spec is arcane with fire coming up very close behind it. The problem with arcane is that it requires a massive mana pool which can best be granted from top-notch gear. Before you get that gear, you might end up being fire as it's mana efficiency isn't great but not as horrible as arcane.

frostmage as i remember it was always extremely overpowered they can kill a melee class before they get hit once