Quite simply, yes. Contrary to the beliefs of most theists, specifically Christians, I am not ignorant of all the gods and goddesses floating around. In fact I used to be Christian myself, so please save me the Jesus-loves-you tripe I've heard a thousand times. Christian theology is the exact theology that led me away from theism, so bringing me back into the fold is an exercise in futility.
While I consider it bunk, I know quite a bit about religion. I have read the entire Bible--not all at once in a linear process, mind you, but in bits and pieces over a modest amount of time for such a large book. (How long can a person read Jeremiah before they need to mix it up a bit?) I have also read the Qur'an, or Koran, or whatever you choose to call it. That right there gives me more authority on "holy" texts than 90 percent of all self-proclaimed Christians. That's right.
Christians in particular find it absolutely unacceptable for me to reject their deity. HYPOCRISY ALERT!! How many Christians reject Islam but know nothing about it? How many Christians look down on atheists, when the average atheist knows more about Christianity than the average Christian does? (Note: I have no evidence to back this up, but it is the general impression one receives from virtually any atheism chat or message board.)
Besides my perceived ignorance, Christians also make the mistake of assuming that I chose these beliefs, which I did not. No one chooses to become part of the most hated minority in the country. I suppose this assumption comes from the trite Pascal's Wager. Here's a news flash: converting to Christianity or dropping it is not a simple choice. A person cannot suddenly decide, "Today I'm going to stop believing in my god. Well, that's that." Give that one a try sometime.
Changing beliefs requires a good reason. One can certainly stop attending a church or a religious activity by choice, but that has nothing to do with beliefs. Deep, personal convictions about life and the universe are the most important freedom anyone has. Period. These things do not change on a whim, or by personal choice. It requires a strong questioning of your original beliefs, and solid evidence that something is wrong.
What is that solid evidence that led me to change my beliefs? The one thing? Well, nothing. And everything. There is rarely a Silver Bullet with these types of transitions. I can post some of the reasons here on this site. I don't know if there was one of them that was most responsible (maybe Free Will), or just a collective atmosphere of doubt, but something did it.
Who knows? The point is, I feel justified to myself. That's all that really matters when considering such deep, personal convictions.