SF Signal has a great discussion up titled Is Science Fiction Antithetical to Religion? Among the authors taking part are Mike Resnick, Lou Anders, Ben Bova, and many many more. And don't even begin to assume that you know what the different authors are going to say. As Resnick states at the beginning, "You can't generalize about this large a field. For every atheist or agnostic author you can name, I'll name a religious one. For example: Gene Wolfe is a devout Catholic. Ray Lafferty was a devout Catholic. Avram Davidson was an Orthodox Jew. Michael A. Burstein is an Orthodox Jew. Ect. Ect. Ect."