[EDIT: just noticed this post is over 2 years old... oops!]
Been working on designing my elementalist (fire & frost) mage design... geared for PvP.
Basic Build
http://www.wowhead.com/?talent=oZfVcfoh0zZAI0uobuhbd
Key features: Pyroblast, Improved Scorch (main dmg spell), Blast wave (knock back AOE), Icy Veins, Cold Snap, and Ice Barrier.
Frost Strong Build (basic + frost)
http://www.wowhead.com/?talent=oZfVc...AI0IobuIbd0dsx
Key features: (same as basic build), Improved water elemental!, and some other stuff.
Fire Strong Build (basic + fire + couple frost)
http://www.wowhead.com/?talent=oZfVc...bZAI0uobuhrd0b
Key features: (same as basic build), Combustion, increased damage stuff.
Not sure what I want! haha.
I'm currently (ever since the new trees) a Fire Mage. I was always a Frost Mage before. I'm considering giving up my current build for this... I'm mostly just trading the ability to have instant cast Pyroblasts (which are really nice!) and living bomb (which isn't as wonderful as I thought it'd be, although not horrible... it's won me some PVP battles where I just kept casting it and running from the enemy!!), and some increased damage talents... for better protection and an elemental. :-)
As for the elementalist build above... seems more PvE oriented... I like PvP :-)
[EDIT] Notes: main damage spell is Scorch (hence improved scorch). I don't use fireball usually but with the brain freeze talent I guess I'll cast an instant one every once in a while. Frost is used to control the enemy and protect yourself.
[EDIT] Ok, after reviewing it, I edited it some more. Realized that since I won't be spamming frost spell, the winter's chill was kinda worthless. So I put those points into frozen core for the spell protection. Also, don't really need flame throwing since most of my fighting will be relatively close to take advantage of blastwave, frost nova, cone of cold, etc. With scorch and defensive spells (ice barrier, frost nova, blast wave, water elemental freeze spell) I should be able to stay very mobile.
[EDIT] Combine Major Glyphs: Water Elemental (reduces cooldown 30 more seconds!), Improved Scorch (adds 3 Improved Scorches each hit instead of 1), and either: Evocation (hp & mana regen), Ice Block (if you love your frost novas), or Icy Veins (remove movement and spell casting slowing effects). Minor Glyphs: doesn't really matter. I like the slow fall one, and the frost & fire ward ones look "ok." But none really matter.