It's high time there's another post.
A major turning point for my atheism was when I started to think about a concept I'll call "divine intervention." For our purposes, divine intervention is the possibility that God intervenes in human life. This can be in either a micro-managing parent view or just as a salesperson/encouraging guide type.
I personally, refuse to accept the fact that there is any sort of intervention from any supernatural being. To me, this intervention would cause a contortion of free will.
In Biblical times, God played a pretty active role. Like after Cain's fratricide, God comes down and asks Cain about the whereabouts of his brother. Now to me, God allowed Cain the opportunity to own up to what he had done, but by coming down to Cain while he was in a crazed state warped Cain's sense of choice. Given the opportunity to think clearly, Cain may have been able to properly atest to his crime.
So if you're the type of theist who believes that by praying to God, God takes an active role in your life and the lives of every human being, answer this: When God solves your problem, or grants you wish, is God somehow denying the right of free will to another person? If you think about it, if every religion considers themselves the "chosen people," we're all on an equal plane. Since the pure contradiction of having all religiously affiliated peoples be "chosen" is obvious. If we're all equal, than how can God play a neutral role in the lives of people. People hate, kill and hurt each other, that's what they do. So at some point, God takes sides.
I would love to start a dialogue on this.