If a child told me that someone touched their "noon" or "winkle" I would have absolutely no idea what they were talking about, but maybe that is just where I live.
I will be using the proper names for those body parts, not necessarily because I want her to be able to accurately describe where she was touched if god forbid that ever happened, but because I don't want to portray her genitals as being awkward or embarrassing. To me, using a cutesy name and being uncomfortable myself with the real name for her parts is teaching her that her genitals are something to be embarrassed of and they shouldn't be talked about. I want her to be comfortable with her body, to know what her body is for, and to be able to discuss with me any problems or concerns she is having (medical or otherwise) that might involve her breasts or genitals. For me it's about treating her "private parts" as just another part of her body, so when she gets older and gets her period or gets a yeast infection or whatnot she feels just as comfortable talking to me about that as she does telling me she has a stomach ache or a sore shoulder. My own mother never discussed our genitals or referred to them at all growing up, she certainly never used the term vagina, and I never felt comfortable talking to her about my period or anything sexual. I remember getting a yeast infection when I was in high school and I saved up my allowance for a few weeks (all the while in agony!) to buy monistat for myself because I was too embarrassed to ask my mom to buy it for me. I never told my mom when I started my period because it would have been awkward and embarrassing and I had to figure it all out for myself. I want as much as possible to take the awkwardness out of these things for my own daughter.
If I ever need to discuss genitals for some reason with my OH or my doctor or whoever I always use the proper terms. I personally would feel very immature referring to my vagina as my "fanny" or something. My OH also uses the proper terms, just the other day he changed Isla's diaper and told me she had a slight rash on her labia. We don't cringe or feel awkward using the proper terms because there is nothing awkward or cringe worthy about having labia! It's normal in our household and I like it that way!