I never read the book or was really aware of it before. I've seen the two previous versions of the story, Last man on earth & Omega man, and liked both. The thing that bothers me most about the ending wasn't the religous overtones, it was he was so prepared everywhere else, yet he couldn't make a safe area or easy escape route. ***SPOILER ALERT*** the hand grenade was powerful enough to kill everyone and him yet he couldn't through it the the busted plexiglass, PLEXIGLASS!! c'mon, kill everyone and escape with the girl. It was all those little issues and more that were turned into a big question mark. Also, how come the infected seemed so stupid, yet they could set the same trap after watching him do it once -I'd have problems making that trap, and I've seen similar ones in lots of movies.
All that said, I'll buy it when it comes out and watch it several times. Overall I still enjoyed the movie and recommend it to people.
Jack