On the one hand, it would be nice to have conclusive proof that homosexuality is not a choice, but instead is an inate characteristic. This would not sway the hard-liners, but I think a majority of people would agree that gays deserve equal protection under the laws including the right to marry, adopt children, recieve domestic benefits, and be protected from discrimination in the workplace.
On the other hand, if research determines the cause of homosexuality, it may be possible to genetically screen homosexuals from the population. However you feel about gays, you probably agree that eugenics is not acceptable.
The CNN article mentions that the scientist believes exposure to hormones while still in the womb is what causes differences in sexual preference. Just watch -- the cause of homosexuality won't turn out to be genetic. It'll be that your mom ate too many Doritos or something.