You gain; A natural attack- 2 small (dagger sized) claws or 1 short (shortsword sized) claw, horn, tail, etc. And a special ability- poison, flee etc.
It takes 30 seconds to change forms, you change forms completely. Once tansformed into your animal totem You can use no skills, can not use any weapons, armor, shields, potions, equipment. It melds into the body. If druid goes unconiuousness they revert back to their human shape. Takes 30 seconds to transform into, and out of, totem animal.
While in animal form you can not speak, but can understand whats going on around you. Your LP's stay the same. Lets remember the skill is called 'Emulate Totem' not 'Become a Bad-Ass'
While as animal, you must wear an NPC sash. (This one wasnt required at the time, but is a good idea non the less)
The abilities of the chosen animals have already been writen up for our own stats should we run plots/encounters with them. It is a small matter to adapt them. Once they have been set for that animal, they will not be changed. If we end up with 100 Fox Druids, rest assured they will all have the exact same ability. (Of course if we end up with 100 of them its obviously too powerful

As I said, this is how it work 'as it stands'. I think that it works very well and am personally very against changing it.
Footnote; the benifit of a quality helmet would be that it would be enchantable. Eric is correct in that a quality helmet gains NO armor bonus.