We're getting pretty far with all the DPS specs, and many of the tank specs. At some point I'll have to go into pure-theory mode (ok, to be fair I've healed one or two dungeons as most of the healing specs - possibly never Shamans) with healers, but let's knock out the rest of the DPS'ers.
Fire Mages, like their Frosty and Arcane brethren, are not getting huge changes because, well, Mages in general have been pretty fun to play and true to their class and spec fantasies for a long time. In fact, you could argue that a lot of the changes coming are sort of to bring the other classes up to the elegance and strong design of the Mage.
Fire is getting some new toys and some upgrades to old toys. Probably the biggest change is that Combustion is getting changed from a powerful DoT into a powerful cool down (well, it's always had a cool down, but now it's more of a buff than an attack.) There's also a cool and very flavorful change to the Ignite Mastery which we'll get to.
So let's get into the Fire spells. As always, remember that this is based on an Alpha build, and while I don't expect to see the baseline Mage spells change too much given how little they're changing from the existing design, you never know.
Fireball is, of course, the primary filler spell you'll be casting most of the time. It has a 2.25 second cast time and deals fire damage to the target.
Pyroblast has a (baseline) 4.5 second cast time, dealing a massive amount of fire damage to the target.
Hot Streak is a passive causing your next Pyroblast or Flamestrike to be instant if you get two critical strikes from direct-damage spells in a row.
Enhanced Pyrotechnics is a fun passive that makes each Fireball that does not give you a critical strike give you a 10% increased critical strike chance, stacking up indefinitely, but ending once you do get a critical strike. I love this, because it ensures you never go too long without a crit.
Inferno Blast has 2 charges on a 12-second recharge, dealing a modest amount of fire damage to the target, but always critically striking. It is not on the global cool down and can be cast while casting other spells. Its main purpose, I think, other than giving you something to cast on the move, is a guaranteed Hot Streak once you've crit with Fireball.
Combustion has a 2-minute cool down, increasing you crit chance by 100% for 10 seconds, and gives you Mastery equal to your critical strike rating (it doesn't double-dip on its own buff, but it makes all the crit on your gear still worth something while it's up.)
Molten Armor gives you an extra 15% crit chance and reduces incoming physical damage by 6%, giving you a nice healthy baseline before you start stacking up crit (I think base crit without anything is 10%, so that's a baseline of 25%.)
Scorch has a 1.5-second castime, dealing a small amount of fire damage to the target, but is usable while moving, which is probably the only time you ever want to use it.
Flamestrike has a 4-second cast time dealing a fair amount of fire damage to anyone standing in it and slowing them by 50% for 8 seconds.
Critical Mass is a passive that multiplies the critical strike chance of Fireball, Scorch, and Pyroblast by 1.3.
Dragon's Breath is an instant-cast spell on a 20-second cool down, dealing relatively low fire damage to enemies in a cone in front of you and disorienting them for 4 seconds, though this effect breaks on any damage. It replaces Cone of Cold.
Mastery: Ignite causes Fireball, Pyroblast, Scorch, Inferno Blast, and Flamestrike to add a 9-second DoT to the target based on your Mastery and the damage of the initial spell. Subsequent applications of Ignite will roll over, so you'll get the full Ignite effect off of each spell without worrying about "overwriting." Also, every 2 seconds, Ignite has a chance to spread to a new nearby enemy.
So as you can see, most of this is familiar, but won't have to worry about finding the perfect sweet spot for Combustion - in fact, Combustion will basically turn you into a Pyroblast machine gun. Before we get into talents and artifact traits (which will add new parts to the rotation,) here's what we're looking at:
1. Pyroblast if there's a Hot Streak.
2. Inferno Blast if you have the "Warming Up" buff - basically if you just crit.
AoE's kind of interesting. With Ignite now spreading, you might be able to just keep up the single-target rotation on two or possibly three targets. But at some point you'll want to start using Flamestrike instead of Pyroblast. With a similarly really-long cast-time, you'll probably only want to use Flamestrike 4 seconds before the pull or if you get a Hot Streak proc. Scorch is obviously the substitute for Fireball when you're on the move, but everything else should be instant-cast in your rotation, so you just swap it out. And of course, you'll now just want to use Combustion on cool down - no prep required.