Tankspot
Not by any stretch a comprehensive guide, but there seem to be a lot of the same mage questions and I figure it'll be easier to answer them in one place.
Spec
Two are equally viable:
• Fire 18/51/0+2. Put the 2 extra points in Flame Throwing unless you have a good fight-specific reason for something else.
• Arcane 57/3/11. Can move 2 Ice Shards points to Frost Warding, and trade points between Arcane Stability and Arcane Focus depending on how much hit vs pushback prevention you need. This is a good raid compromise with 3/5 Arcane Stability giving 100% pushback prevention with Imp. Concentration Aura.
• Correct glyphs are in the links above, there are no options.
Spell Rotation/Priority
Fire Priority: LB -> HS Pyro -> Fireball. Keep up scorch debuff if you don't have a warlock providing it.
Arcane Rotation: ABspam04MBAM. With 2pcT10 switch to ABspam0234MBAM. If you get super unlucky with procs clear the stack with (a non-MB) AM.
Gear
Use Rawr. It is the best model of mage combat around. To begin, load your toon from armory, tick all the buffs you have. Watch the video on the Rawr site.
"Optimal" gear discussion can be found in this thread on ElitistJerks.
Stats
Hit cap yourself, 17% total from talents, buffs/debuffs and gear. Priority is vaguely:
Fire: (Hit to cap) > SP > Crit > Haste
Arcane: (Hit to cap) > SP = Haste > Crit
Use Rawr for your individual case and to plan gemming and enchanting.
Cooldowns
Mirror Image is on the GCD. Don't macro it in with other cooldowns because you will waste up to 1.5 seconds of them while the GCD expires. Hit MI, then once the GCD expires hit your macro containing the other abilities and AB-cast.
Fire: Combustion and Quad Core (4pcT10 MI).
Use Combustion with Quad Core always. You want to use QC: (a) during heroism, (b) below 35% boss HP, and (c) as many times as possible.
Arcane: Arcane Power, Icy Veins, Speed Pot and Quad Core.
In the absence of Heroism(/Bloodlust) this is easy: Quad Core+IV+AP+Pot up front, then AP as soon as it's available, then wait for AP to do QC+IV+AP together.
With Heroism in the mix you must avoid GCD capping yourself, so how many abilities you can stack inside Heroism depends on your haste rating (assuming full raid buffs and black magic enchant here).
With 2pcT10.
<564 haste - AP+IV+QC inside hero, lone AP, AP+IV+QC+Pot outside.
564-882 haste = QC+AP+Pot inside hero, lone AP, lone IV, AP+IV+QC outside.
>882 haste = QC+AP inside hero, AP+IV outside, AP+IV+QC+pot outside.
Procs
You will have procs from things like Lightweave, Black Magic, ICC rep ring, and trinkets. Amazing mages will time their cooldowns for when these are going to proc. Popping everything up front mostly gives you at least one coincidence.