i chose this same lineup, the 4 powerpacked shamans with the +5crit bonus would be crazy. Ive also seen videos on balance druids tanking gruul's, so they arent so squishy in moonkin form.
The videos ive watched of past players shows that with elemental totems there isnt alot of need for tanks and healers and flat dps works well. Im not going to spec any kind of -theat talents for my druid, but i will for the shamans. Just so i can organise my agro a bit better if there is need.
Also I am going to downrank all my heals and have the 4xshamans healing the moonkin to full and the cheapest possible mana with little overhealing.
Have one of your shamans spec 41 in elemental and the others with 40 elemental and 21 resto for natures swiftness, its great pve/pvp burst damage to have those 3 with NS. And totem of wrath doesnt stack.
Thats my plan once i hit 70, time will tell weather im prepared or not.