BTW, why on earth would ANYONE want to wear stilettos? Besides being extremely bad for the feet, causing potentially permanent damage to the achilles tendon and forming bunions, these shoes are designed specifically to be NON-tzniusdig. Their nickname is a very profane expression.
I am a little surprised to see frum women everywhere, wearing these (I am not being judgmental here, just taking note of the fact that this is not what I would typically expect to see on the many Yeshivish young women I see at Simchas, based on their feelings about tznius). About the only thing I can think of in their zechus is that if you are attacked by a mugger while wearing them, they make a good weapon.