I used to think that Dawkins & co's books were just preaching to the choir. Yeah, I found them fun to read and nod along, but I didn't believe they'd change anyone's mind. I assume that this isn't an issue of logic, and when you're not dealing with logic for the most part, no logical argument would be sufficient.
Reading posts like these do make me believe that it's possible to change minds, if people are willing.
(I'm not saying those books aren't useful; they give a sense of legitimacy to those who don't side with religion and this is important.)