The thing you've got to remember here is that some people are far more up front and honest about sex than others - they enjoy what they do, its exciting and natural to them, they probably dont think much differently of it than a lover of good food thinks of telling all their friends about the great meals they've had. Their world view may be totally different to yours - to them, sex may be something to share, to reveal rather than conceal, something that makes good stories, just as we tell stories about our emotional adventures. Intimacy is not such a private thing for such people.
If you friend is one of these very open,casually sexual people then she probably isnt aware that she is making some people uncomfortable with her tale telling. She probably finds it a nice girly bonding thing to do, so that you can all laugh and relive it with her and share the things she enjoys in life. Have a quiet word with her about how this makes YOU feel. This isnt about wether or not people view her as a slut - her life choices are her own and people shouldnt be so narrow minded about adventourous attitudes - its not as if she's cheating on a husband, deceiving or hurting anyone. safe Conventional relationships work for some, Innovative, experimental relationships work for others - its not fair for people to brand your friend a slut as they do not mean this in a kind way. If she has sense and confidence she wont mind what such conservative thinkers mutter behind her back. Im sure if they wanted to debate with her in an upfront way the pro's and con's of her life style choice she would do so happily - its the sneaky name calling thats so offensive.
I know it dosent pay to offend others - so perhaps you could help your friend work out which of her aquaintences are offened by this behaviour and which are not. I dont suppose she'd want to tell these stories in order to shock or upset anyone, and she'll understand your good intentions if you tell her all that you told us in your post.
On the other hand, if this life style is making her or her partners hurt or unhappy, or if she is taking dangerous risks with her sexual health and personal saftey then that is another matter entirely and you would be wise to advise her to curb her behaviour.