The Priest, 2x Mage, 2x Warlock is the dynamic I am currently using.

Heaps of fun, PVP Power house, and a part of the best taxi service in the game.
Portal to Orgrimmar, Summon back! It should be illegal!

Combat looks a bit like this as far as cast sequencing goes:

<NUKE>
Priest: Mindblast,smite
Mage: Pyroblast, Fireball, Fire Blast
Warlock: Shadowbolt

<DOT>
Priest: SW:Pain, ,Holy Fire,
Mage: Scorch, Scorch, Scorch, Fire Blast
Warlock: CoA (One lock casts CoElements),Coruption, Siphon Life,,
the extra "," turn this into a four step macro before it repeats itself

<AOE SPAM>
Priest: Holy Nova
Mage: Arcane Explosion

<AOE DAMAGE>
Priest: Prayer of Healing
Mage: Blast Wave, Arcane Explosion
Warlock: Hellfire :twisted:

<FROST NOVA ROTATION>
MAGE1: /castsequence reset=24 Frost Nova,
MAGE2: /castsequence reset=24 ,Frost Nova
with both on a 24 second reset there will allways be 2x frost novas ready to go

<CROWD CONTROL> I use focus for targeting information.
The Priest Has 4 Hotkeys for each slave:
/SetRaidTargetIcon("target",x) "x" being a number 1 to 9 for lucky charms
the same hotkey is bound on the Slaves to
/assist Priest
/focus
another hotkey bound on the mages reads like
/target [target=focus]
/cast Polymorph
and another on the warlock reads like
/target [target=focus]
/cast seduction

<BUFF ME>
Buffs are done with a common bound key. in my case its G4 on my Logitech G15 Keyboard.
Priest selects the party member, hits her commonly bound /assist key, then hits G4, an everyone casts a buff. AI, PW:Fort, Detect Lesser Invis, Underwater Breath.
You get all your buffs at once this way.
It's also helps when your buffing another player out in the world.. this goes a long way to helping sway people who think your a bot.. when was the last time a gold farmer handed out a buff?

As with all my multiboxing at this time, its all still a learning experience. I hope to refine the way i handle combat, crowd control, pvp, dungoen crawling as I continue to level but I hope i helped just a bit.