I like Bill Maher, I think he's pretty funny (although in full honesty, I haven't watched his HBO show much, mostly I remember him from his stand up and "Politically Incorrect"). I'm also (more or less) an atheist, and certainly don't subscribe to any organized religion (ignore the fact that I'm an ordained minister and I talk all the time about being Jewish). So this movie should be right up my alley. And I enjoyed it mostly...but why didn't I really love it?
Maybe it's that it was too much of a one-minded screed, with no mention of any of the good things that religion (or at least, religious people) do. Although I understand and even partially sympathize when he thanks a church group for "being Christ-like, not just Christian" it seems condescending (like Christians are so unlikely to be Christ-like?). Maybe it's that he's too self-satisfied with his "gospel of doubt". Maybe he just wasn't funny enough, trying to let very earnest people hang themselves with the ridiculousness of their faith. This approach worked well in "Borat" (which was also directed by Larry Charles), but that had Sacha Baron Cohen goading the dupes into saying stupid things. Too often Maher lets them say something that he thinks (and frankly, I think) is stupid, but his only response is "C'mon! You can't really believe that!"
All this isn't to say it's not an enjoyable movie. There are many genuinely funny scenes (the old priest in front of the Vatican ranting about how it's all just stories is priceless. I wonder if he's allowed back in the Vatican after this). And while the screed is one-sided, it's not exactly untrue or even unfair. It's just on some level unsatisfying. Like this critique would be more convincing if it came from someone with more sympathy for religion.