I think we take this concept of "overweight" much too far in this country, America. This term is used to compel already anorexic young women to starve themselves even more (so more of their ribs can show) so that they can be considered eligible for runway work.
To be more "practical," to get more to the meat of your question, in the way I suspect you mean it we can say: there are those women who look better with a few extra pounds on them. It seems to me certain actresses are like that. You see them very early in their careers and they are very skinny; but ten years or so later they are much older and have put on a substantial amount of weight and they look MUCH BETTER than they did when they were young -- at least in my eyes. I would say the actress Talia Shire (from the movie "Rocky") fits this bill.
Have you ever noticed female opera singers? Its interesting, they are almost always of a rubinesque build, perhaps technically "overweight." But they almost always wear the weight very well. They are quite attractive. Pehaps it has to do with body type or bone structure, I don't know. I think Paula Dean is an attractive woman (you know, from the Food Network); Ina Garten (from Food Network's "Barefoot Contessa") is a handsome woman, though perhaps technically "overweight".
Remaining on this crude level, we can actually say that there is a difference between a "full-figured" woman and one that is "overweight" (the scale is different from the perspective of different people).
But perhaps you mean something different by "overweight"? Yes, there is another level of meaning we could explore. But that would be impolite, wouldn't it? By the way, I answer this question from the perspective of a heterosexual (or what is insultingly called "straight") male.
Take it easy. Thanks for the question.