It was OK, but I wasn't terribly impressed. I will say it was hard for me to get immersed in scenes attempting to instill a sense of loneliness in the vastness of space when such silent scenes were punctuated by the sounds of people munching on popcorn all around me.
Re: religious themes, there was a bunch of symbolism. At one point, Sandra Bullock curls up into a fetal position and passes out. As she floats in front of a porthole, it's as if she's an embryo. Bullock is driven by memories of a tragic loss, but the extraordinary circumstances she's placed in give her a newfound determination to live and take her destiny into her own hands.
I don't want to spoil anything, but for those of you who have seen the movie, think about the very end as symbolically representing evolution.
At one point, a frog appeared on-screen and several uber-nerds went into hysterics. I suspect they were laughing about being clever enough to recognize some possible allusion to this incident: http://www.universetoday.com/104679/absolutely-incredible-photo-frog-launches-with-ladee/