The word modesty has extreme connotations with very charged religious and sexual undercurrents, and that was noted by the others who posted. The ideas of exposed skin and sexual charge seem to be connected in the minds of many- and the repression of those thoughts in Christian culture is a discussion for another time and place alltogether.

A survey- I couldn't read too much of it, it was really appalling to me as a Christian and as a woman- gave Christian men an oppurtunity to answer questions about the way women dress on a sliding scale, and then comment. The comments were, in the case of some responders- effectively telling women how to dress, outlining what is appropriate in what situations- and advising women to "be cautious" of anything remotely "tempting". I think that survey effectively ties up the issue of how much of a religious connotation modesty can take on, and goes a step further to say how sexist the ideas of modesty can be... The idea of a woman dresses to please men, or to entrap them... ugh. It's enough to make me pull my hair out.
What I wear should have no bearing on what a man thinks. If he is "tempted", he should keep his thoughts to himself. And those thoughts are just as likely to be there if there's more left to the imagination than if I were a bare-all kind of girl. Sophie mentioned not showing any skin she wouldn't want touched in a social setting, and I have to note that no man has a right to infringe on my personal space in any way I would find uncomfortable, bare skin or not. How I dress shouldn't make me an object, and any man looking me up and down or forming an opinion of me based on how much or little skin is showing is probably not one I want in my acquaintance. His thoughts are not my responsibility, and I'm not going to dignify the notion of those who show more skin "asking for it" with a response.
Let's step back for a second from the word "modesty". I can't honestly say I ever really think about it outside of the horrible connotations it takes on in a religious sense. When I'm thinking about how things look on me and appear to others, I want to look and feel classy. I want for fit to be as it's meant to be, not painted on or hanging off of me. I want to FEEL good- confident in my curves and lovely in my own skin. If that means I show a bit of cleavage or shoulders or leg, I think I have the right to. It's always been about how what I wear makes me feel. I'll wear a bikini on the beach to feel the sun on my skin and a wiggle dress in church or at work because it makes me feel sassy. I'll put tights on not to cover up, but because I like what the texture and color add to an outfit. A suit or a cocktail dress aren't worn to catch the eye, but because they make me feel good.
Women dress for women, first and foremost. We look each other up and down, and my sorority sisters and other women I trust have more influence over how I dress and are able to give me more of a confidence boost than anything a guy can say. I can't tell you how many amazing women I call friends and sisters I trust keep these rules or some like them in mind... I'll leave you with their words of wisdom:
- Knee-length skirts are MUCH sexier than miniskirts in many situations, and the elegance that comes with them is something desirable.
- Baring leg and shoulder/chest in one outfit is baring too much. Some of either is wonderful.
- The saying "If you've got it, flaunt it" doesn't mean bare it all.
- No matter the outfit, keep the place you're going in mind, and keep it classy!
These are my thoughts as a moderately liberal individual with feminist sensibilities... I'd really enjoy hearing your thoughts, and even more, I'd like to say again I had absolutely NO intention of offending with mine.