Fifty shades of what?!

Everyone and their mother (well definitely not my mother, I can assure you that) is reading Fifty Shades of Grey.  From what I have heard about the book I am completely shocked it is so mainstream.  I have read a few articles about it now and have heard it repeatedly referred to as "Mommy porn."  My friend (who shall remain nameless) is reading it and put it perfectly when she said "Nicholas Sparks is mommy porn, this is hardcore porn!"  I had another friend say she had to stop reading it for a few days because she was disturbed and felt dirty.  I am not a prude per say but grew up in a very strict household in terms of what we were allowed to watch and I feel like I will hear my mother's voice as I read it asking me why I'm reading this trash and where has the morality gone in this country?!  I can't say I disagree with her on that.  I am constantly saying that I am terrified for my children to grow up in a country where morals seem to be completely lost.  Also, where are the novels where women are potrayed in a strong, independent light and why aren't they popular?!  I could rant all day on these issues so I'll just stop there...