i believe the GCD is 1.5 secs but i could be wrong.
my main macro is
Code:
/castsequence reset=15 Mana Spring Totem, Wrath of Air Totem, Stoneskin Totem, Magma Totem
not sure on the spelling, I'm at work, but you get the idea.
That macro is bound to "a". I use s,e,d,f as my direction keys. allowing me to use q, a, z as macros and other spells.
Gennerally if I am soloing a single mob, I don't waste time with totems, I start with lightning bolt, then chain lightning, earth shock or fire shock (depending on mob) then hit until dead.