What is The Pin Up Girl Anyway?

There are several definitions of the noun Pin Up Girl but the most accurate/basic one I found was this:

~a woman whose glamorous qualities make her a suitable subject for a pin up. Many pin-ups were photographs of celebrities who were considered sex symbols. Other pin-ups were artwork, often depicting idealized versions of what some thought a particularly beautiful or attractive woman should look like. 

It is the playful and sensual nature of the 1940's Pin Up Girl that I find appealing. The photos/drawings were suggestive, of course, yet tasteful and there was something left to the imagination. My mother recalls, as a child, seeing the Pin Up Girl images on cigarette packages, for example, and remembers them being so risque. The Pin Ups of the late 50's and 60's were even more risque than the ones of the 1940's and that's why I chose the 1940's Pin Up. I am not interested in strapping twirling tassels onto these almost 40- year-old breasts. I think that leaving a lot to the imagination is the key to sensuality. I think that having intelligence and a strong opinion and a voice is far sexier than allowing oneself to be silenced or to constantly be striving for society's limited ideal of beauty. Of course, physical appearance has something to do with it but I really wonder if things like confidence, humour, strength, intellect, and so on have more to do with sex appeal than we think. Have you ever met someone who was a gorgeous specimen of a human being and then as soon as they opened their mouth, they lost all appeal?
I have found it interesting that since starting this project, I have been told things like, "You're fine as you are." or "You don't need to lose weight." along with suggestions that what I am doing is buying into the pressures of society and its ideals of beauty. While I appreciate these comments shared out of kindness, I do want to be clear that I am actually quite content with myself both physically and otherwise. I happily walk around naked and feel no shame whatsoever about my 39-year old body with all of its imperfections. This body has served me well.
With that said, I don't think there is anything wrong with moving towards a healthier weight or incorporating exercise in one's life. We are all very familiar by now with the benefits of daily movement for our bodies and our minds. It boils down to the reasons why one is losing weight or exercising. This project is simply a fun journey into my 40's and being the best I can be as I enter this next decade.