Thanks for the posts and emails (sorry the comment function didn't work for so many of you... what can I say, cakes are my thing, not computers!)
So, the answers to the game (how many of the below went into my cake serving 215 this June):
Butter: 16.5 sticks (over 4 lbs!)
Pow Sugar: 12 lbs
And the winners are:
Stephanie guessed 40 eggs
Rebecca and Amy TIED guessing 16 sticks of butter
AND Rebecca guessed right on with 12 lbs of powdered sugar!!
Congrats girls!! Now I know who to call when I'm overwhelmed with orders :) I'll be in touch for delivery of a box of delicious cake truffles.