Have noticed these distinctions also, Patrick. The generation gap is particularly obvious here in Tulsa. Few (if any) younger folks care for the simplistic "believer/non-believer" division so popular with many older adults. They have a refreshingly nebulous faith and make accommodations for others. Also have noted the hyper-religiosity of many minorities, the worse experience I've had here in Tulsa was when I admitted to a black woman that I'm an Atheist. She was so angry I worried it would devolve into an altercation.
Yeah, anyone around here past thirty is pretty well set in cement where it concerns religion, that's for sure.