OK, I'm a level 43 with good skills.  I play my character well, pull well, stay alive alone, regularly fight mobs two levels above.

I've tried the AOE grinding, and it just doesn't seem to have a payoff for me.  I seem to do more corpse runs than most people lead me to believe you should if you do it right, but even when things go well my XP per hour is just not worth the hassle (and boredom of going back to an area you ground out 5 levels ago).  And, I just don't feel right asking a priest to help when we could go up a few levels and get a better payoff and have more fun.

Am I doing it wrong?  What's the payoff?  Discuss.

I've never tried aoe grinding, personally, though I use it in instances and helping out lower level characters all the time. I think for proper aoe leveling, you need the right place and the right talent spec. And a number of the good aoe grind spots, like east wing dire maul, have been changed so they no longer work.

I personally love AOE! It helps me lvl so much faster. Just round up everything in the area (having a mount helps here), freeze them, and then AOE the hell outta them. They're always dead before they get to me. Quite helpful.

Try AOE grinding green level mobs that are mostly (if not all) melee. Caster and ranged mobs muddle things up. In my opinion however, single target grinding is much more efficient for a sub-60, since dying lowers efficiency by a lot. I recommend frost spec for grinding as well.

If you have Magic Absorption, casters wouldn't particularly be a bad thing =p

Although, I've never AoE-grinded while leveling, I've played around with it elsewhere and Resisting spells to gain mana back is a godsend.

I'm not sure what spec you are but frost makes it much easier to AoE grind as long as you have improved Blizzard and what not.

There is a really slick AoE guide on the European WoW site, put out by Bangy, you can check it out here Bangy's little guide to Blizz Mage AoE grind. It helped me out tons, now i am cranking out the XP.

Bessarius:
Try AOE grinding green level mobs that are mostly (if not all) melee. Caster and ranged mobs muddle things up. In my opinion however, single target grinding is much more efficient for a sub-60, since dying lowers efficiency by a lot. I recommend frost spec for grinding as well.

As a level 70 was in Shadowmoon doing a quest to kill demon hunters in the training grounds (Aldor version of the quest) that were my level or maybe 1 level below me. I am a frost spec'd mage with all blue armor and green trinkets/ring/necklace. I found I could not handle more than 2 at a time (maybe 4 if I got really lucky) and that took every bit of my mana. So I ask the same question that started this, what am I doing wrong. granted my gear is not great (Aldor rep reward chest and 3 of my set pieces is the best I have), but it seems, trying to AOE just doesn't work. I have tried this several times as I have leveled (always on kill X type quests)and it just never seems to work the way I have heard. So, am I doing something wrong, or is this specifically for grinding green mobs and gaining XP by killing a zillion 15xp mobs as opposed to either grind level appropriate XP or level appropriate drops or completing level appropriate quests? On a side note, I find I can handle 4 or so mobs in the heap in Netherstorm (the ones that drop the Zaxxis insignias) which are close to my level (about 2-3 below me). But it still took everything I had.

aoe is NOT a myth it is a sound way to level at a high rate; provided you understand what you are trying to accomplish.
Aoe is not for questing at level 70.
Aoe IS for producing rapid leveling by aoe'ing non-caster mobs that are 1-2 levels below your mages level.
Aoe is also very good for farming certain mats; again with the caveat that its non-caster mobs.
Aoe has specific needs to function well and cannot be used in all situations nor at all times. The best method for completion must be used at all times.
For instance, plaugelands, skeletons in graveyard, or the fields, easy pickin's for aoe; real easy. That being said there are a few casters that would tend to mess things up a bit.
Lousy aoe, ANY ELITE thats NOT 20 levels below you. You just run out of mana and they still keep coming.

Aoe is great if used when circumstances allow it; other wise just use standard kill tactics.
Aoe is NOT anything super, or perfect, nor even useable that often but when it is; use it.