Are women attracted to intelligence, and how big of a deal is physical attractiveness?

I tend to consider myself to be an intelligent guy. I graduated in the top ten people of my class and I am majoring in Applied Physics (math intensive). I am quite pleased with my mental ability, but I am on the large side in terms of weight. I have only had one girlfriend to date, and that ended over two years ago. I am curious as to whether or not my weight could be an issue and if women are attracted to intelligent men.