I would do a loot "council" with a healer a tank and a dps who I trust and who knows the other classes as well in case I was in doubt of who I'd want to give each item to.
I'd also enforce a DPS > Tank > Heal priority on loot as that's what's best for progress.
Oh and people should link the item(s) they're replacing as well as any set bonuses lost/gained and if then off-set items that they might be able to use after breaking a bonus etc.