Personally I like Maher's show. It's a comedy show, light on policy and sometimes the panel is absolutely atrocious...but in any event say what you want about him but he is terribly unlikely to pander to the right under any circumstances.
And he is also right for the most part in what he says. While there are some fringe Christian groups in Africa that go nuts...they're fairly self contained on a continent nobody cares about. I'm sure if you looked hard enough you could find other examples. But the bottom line is Islam is the least tolerant of the major religions. That's all he's really saying imo, and that's the truth in 2013. That isn't to say that adding the caveat that there are a TON of muslims world wide who are not terrorists isn't important, particularly for public officials. Not just for political reasons...but b/c the muslim fringe is nuts...and it's better to speak softly and carry a big stick given the way in which they wage war.