As a part-time mage who usually plays meatshields, let me just add something here re:kiting.

If a pull goes bad and you're kiting something around, and the tank makes an effort to get it back by taunting, either let him know you're kiting and ok, or let him have it back. Nothing is more frustrating than taunting a mob off a caster DPS only to have said caster keep nuking and peel the mob off me again. A taunt only gives me 110% of your aggro. One or two more spells will bring him running right back to you again.

A tank's job is to keep pulls under control so that squishies like you can stay alive and keep burning, freezing, or arcane-ing things to death. If I think that mob is running around willy-nilly, I'm going to do everything I can to get it back. If you have it under control, most tank are fine with letting you kite it. One less mob for me to worry about.

So please please either let the tank know you're kiting, or let him get the mob back. I'm not going to keep wasting a taunt cooldown trying to get a mob back if you're not going to cooperate with me :P

Not to mention the more time you spend trying to get a mob back from someone the more likely you are to lose another. 90% of the time a pull falls apart starts with one mob breaking from the tank and the tank waste too much time and resources trying to take it back.

I'll second what Snuzzle has said. As a tank who dabbles in the mage class, the old adage since Vanilla of, "run to the tank if you pull aggro" is you're safest bet & your tank, whether a full time meatshield or part-timer will recognize your efforts & remember that you're concerned with utility & dps. That being said, I'm aware that being in melee is extremely dangerous in Cataclysm (as Rossi has pointed out repeatedly in his columns), but good maging can be as easy as 'blink', 'ice block' @ the tank's location, allowing them to reaquire mobs while you get to safety.