Okay, i switched to arcane from frost on my caster dps team (shammy, pally, boomkin, mage) and OMG the damage output is so much higher. Frostspec lusted with all buffs was about 3500-4000 dps plus pet of 700 dps. Arcane, all buffs for the period of one lust, anywhere from 7500 dps min to 10,000 max that I saw. the mana efficiency is terrible but a full mana bar can easily pump out 350k damage very quickly, you could pot or evocate after that if you were in a raid or something but dam, i was impressed.
I used click macro for arcane blast and also arcane missiles. I found i had to add [nochanneling] to the spell after arcane missiles or it would clip the last missile even though i had [nochanneling] on arcane missile spell. Dps testing was on the heroic training dummy in org.
Buffed with standar d buffs and totems my mage is at about 2750 spell damage