I read that study. It's a little inaccurate as well as misleading to bottle up sexuality as simply a response to stimuli.
This study's method monitored physical reactions that people have no control over. Even when the body is forced into nonconsensual intercourse there is a physical reactions taking place. So sure, women responded in a way to viewing sexual stimulus. But sexuality goes beyond that, and I'd disagree to the reduced conclusion that all women are gay because of it. As much as I'd like to believe it.
Take the conclusion with a hefty dash of salt.