Example: A level 8 druid can wild shape into a Violet Fungus and can use its Poison special attack.
What would the DC of the poison be? According to the Polymorph subschool boilerplate, turning into a plant with Plant Shape I means that the poison DC would be the DC of the spell Plant Shape I (i.e. 15 + Int for a wizard, plus any bonuses for Spell Focus, etc.). But in this case, Wild Shape is a (Su) ability. So would it be 15 + Wis (as if it were a druid spell)? Or 15 + Cha (because (Su) abilities are sometimes based on Cha)? Or 10 + 1/2 HD + Con (as implied by the violet fungus description)?
Same problem with the abilites gained from Elemental Form(s). What is exactly the DC of a Burn ability of a Medium Fire Elemental Wildshaped Druid? Or the DC of the Whirlwind ability of a Large Air Elemental Wildshaped Druid?
I currently use the DCs of the abilities of the 'basic' Elemental from the SRD, minus the relevant ability of the original Elemental, plus the relevant ability of the Wildshaped Druid (for example, a Medium Fire Elemental has Constitution 14 and his Burn ability - which is Constitution based - is DC 14; a Wildshaped Druid with Constitution 18 would have a Burn DC 16), but I'm not sure if this is the currect interpretation...
As a side note, somebody (I really don't remember who) pointed out that the enhancement bonus given to the base land speed of a creature who changes form into a Fire Elemental (thanks to Wild Shape or Elemental Body I-IV) changes the basic rules of the Polymorphing subschool spells, which says that "Your base speed changes to match that of the form you assume." (page 159).
So, what is exactly the land speed of a Human Druid (Spd 30) who Wild-shapes into a Huge Fire Elemental? 50 feet (the base Druid speed plus 20 feet, as indicated in Elemental Body IV), 60 feet (as per the 'base' Huge Fire Elemental), or 80 feet (base Huge Fire Elemental PLUS bonus from Elemental Body IV/Wild Shape) ?