Replying to How different are womens boots to mens?(not looking for reccomendations, bootfitter!)

before you get riled up with not another boots thread. im not looking for somebody who knows nothing about my friend or her feet or needs to "recommend" a boot to get i am not going to let her make any decisions without getting properly fitted. I am helping one of my friends to get a new setup and i was wondering what are the fundamental differences between mens and womens ski boots? i know there are definately different ergonomics to womens and mens calves and feet but not clear on the details.