Gearing for hit or haste?

[Tonyx]

I confirm that, for heroics, anything over 6% (accounting the 3% from talents) is totally wasted.

[Simulacra]

thx awesomesauce

[Dominian]

Beeing hit capped even just for heroics is the biggest upgrade an elemental shaman have!

The elitists claim that after beeing hit capped and having 2200 spelldamage you should aim for 550ish haste rating.

actually, at one point, maybe with epic gems, we will start gearing for haste again, just like tbc, for now 19 spl dmg gem is better than 16 haste, in full ulduar gear haste will scale better than spell power. 9 spell power and 8 haste might be the answer here.
The point was to have 508 haste to be able to squeeze another LB into Your rotation, no matter what Your spell damage is.

Yeah the haste part was mainly due to the extra LB instead of a CL, stacking for more would be wasted since doing a LB over a LvB will lower our dps.

[Catamer]

hit,crit,haste and how they stack up
hit prevents a miss, any miss is bad because it could have been a crit and you wasted time casting.
but hit has a diminished returns, once you aren't missing having extra hit doesn't help you.

crit and haste work almost the same
a 10% crit 0% haste means you have the dmg of 110 casts at the cost of 100 casts ( mana cost of 100 casts )
a 0% crit and a 10% haste means you have the dmg of 110casts in the time you would normally cast 100 casts ( mana cost of 110 casts )
a 10% crit and a 10% haste mean you have dmg of 121 casts ( 110 casts in the time of 100 casts but 10% were crits) at the mana costs of 110 casts.
having both crit & hast is more than if you only had one of the items such as 20% haste and 0% crit.

now for why haste is consider better than crit.
it takes less haste points to get 1% haste than it takes crit points to get 1% crit.
several classes have special cast sequences that give 100% crit, such as the shaman lava burst after a flame shock so for the shaman having extra crit gives a diminished return when using lava burst.

spell casters:
for the long fight, crit is better than haste because it's more mana efficient.
for the short fight haste is better than crit to get more spells off.
in general you want both because any crit off of a haste cast is a huge bonus.