Since Redafro seems to be striving for other opinions on this topic, I guess I'll throw in my three cents. Hope I'm not insulting anybody.
As you might know, Poland (where I live) is heavily religious. 99% of the population is Christian. You can tell it wasn't easy for me to tell my family I chose to be Atheist, hah. But to the point. When I was younger, I believed in God really strongly - I used to pray every evening, confess, take communions and all that stuff. As I was growing up, I started questioning religion more and more. It seemed weird to me that such a good God would let so many people suffer (e.g. famine and wars in Africa, as Isobel said) and why would he make people suffer in Hell eternally. I started wondering about it because I heard this adjective describing God - "infintely merciful". If he was any merciful at all, he wouldn't let sinners be damned forever. Eternity is a really flippin' long time. I mean, in most cases even judges don't imprison people until their death - and courts by definitions are infinitely less merciful than God. Another thing that really bugged me was the veneration of saints - and especially, their relics. I mean, seriously. If you pray to some piece of BONE that's been in the body of some guy hundreds of years ago, it's better than normal prayer. Moreover, it can heal you. Usual critic of religion followed - I'm not gonna write all of it here - but let me just name evolution of religion, Holy Officium, Inquisition, witch hunting, crusades, superstitions, and so on.
Another thing that surprised me about Christianity is how different was Judaism - which, according to the church, was the religion people should follow before Christ got around - from actual Catholicism. Old Testament God is personal (he's even got a body! If you look at His face, you die! Wtf?) and seems to be super angry and strict, while in the New Testament he's all totally merciful and loving. Jews were supposed to sacrifice cows and other animals to Yahweh. The ritual was decribed in the Bible in exhaustive detail. They also performed circumcision and were totally allowed to have multiple wives and God was cool with it. When Jesus did his stuff on Earth, all of these changed. Why? Why would God-given, supposedly eternal laws change? Couldn't he get it right the first time? Another thing is the deification of Saint Mary. I mean, what the hell is up with her? She's not one of the three consubstantials of God, she's not a regular saint. Nope. She's a flippin' QUEEN OF THE HEAVENS AND THE EARTH. What.
So I read a lot about Christianity and different religions. For a while, I thought I would convert to Protestantism. For some time I thought I was Agnostic. And now, herp derp, I'm Atheist. Honestly, it just seems like the most probable one. So yeah.
TT: I guess one could use those words to describe it.
TT: If armed with a predilection for the inapt.