I would agree with many of the above posters who cite access to information as the primary reason for my disbelief.
That said, one of things that came out of jwism, is the mindset, that religion and spirituality, if it is healthy, MUST be absolutely true. Of course, this is false, to debateable, at best. But nevertheless, we as ex-jws are suspect to this mindset. Where as most people, can just simply accept their belief, (from whatever religious background they have), as sufficient, even if flawed, the ex-jw tends to have a much more difficult time with accepting this type of thought. Religion was always taught to be absolute truth.
Because of this, we search for truth. Eventually, we discover, by hook or by crook, that absolute truth does not rest in religion, of any kind. I consider myself agnostic, borderlineing on atheist. In other words, if I MUST choose where I stand, I don't find any holy book definition of god, adequate. A deist's understanding of god, is so different from any holy book definition, however possible, that one could basically consider this definition of god irrelevant in real world terms. Hence, by that measure, I'm an atheist.
j