In kara, I've gone from my usual GoA to WF instead, and it nearly solved my entire 'shaman steals teh agro' issue, as well as finally putting our token rogue on top of the dmg meter for a while.
we split kara groups between 1 full melee group, and one full caster/healer group, the obvious exception being the tank's pet lock.
the group consists of
-warrior tank
-feral tank
-rogue
-lock
-enhancement shaman
Clearly GoA benefits more members of that group, but for overal performance, wf wins hands-down. More solid MT agro, higher rogue dmg (by a long margin) and lower shaman threat (well probably not that much lower, but 3%-ish less crit

)
With agro more solidly on the tank, I don't have to diesel my dmg so much, so I actually can lay on the spank more than was the case before, while finding myself 'tanking' less.