I do not bike commute (it isn't necessarily more convenient unless I have a late meeting after work). I also didn't bike as an adult till I saw the Cycle Chic book. That helped to push me over the edge of bike-curious.
Here is why:
This showed me I didn't have to alter my normal life to ride a bike. There were people in cute and polished, professional outfits riding a bike.
Prior to that, people I saw riding were either in bike gear or bike optimized outfits that weren't my style. Or just really casual. My personal style is what I'll call a California version of Connecticut preppy work attire. I dress "up" most of the time, weekends included unless I am feeling really lazy. Those images "proved" the a bike could be compatible with my clothing style. It is shallow, but really important to me. I am "girly" in the sense I do not like to get my hands dirty. I do like to know and understand how stuff works and why things are designed the way they are.
I know there are plenty of women like me, on the fence and not sure if biking suits their lifestyle. Like minded role models are critical!
And more focus on non-commute trips. We tend to make it feel like the only way to do it is all or nothing.