I am making a concerted effort not to refer to myself as a "non-believer" anymore. It just isn't an accurate description. I am an atheist, and I prefer to call myself an atheist when discussing matters of religion. "Non-believer" may indeed be an efficient way for referring to atheists, agnostics, secular humanists, freethinkers, and the like collectively, but it strikes me as misleading. In most respects, I am very much a believer. That's right, I believe in all sorts of things.
I have noticed that when religious people refer to "non-believers," they usually do so as a matter of convenience to describe those who call themselves atheists, agnostics, etc. I certainly understand the need for broader terminology, but the label still strikes me as a product of religious privilege. Why must "belief" be equated with "religious belief" as if no other types of belief are as worthy? As an atheist, why should I grant the religious the right to equate "belief" with "religious belief" when we are all believers in something?
And how dare any religious person give me the load of crap about "How can you be an atheist? I can't imagine going through life not believing in anything." I believe in plenty of things other than gods.
In contrast to how the religious use the "non-believer" label, we who are described by it tend to use the term as a socially desirable alternative to other labels. We recognize that "non-believer" is more socially acceptable than "atheist" and less likely to be misunderstood than other labels.
If one was so inclined, one could make the case that atheists who call themselves non-believers do so because they are too afraid to admit what they really think about religion. Of course, one could also point out that there are situations in which one may wish to avoid or simply not have time for the sort of responses elicited by the "atheist" label. One could even argue that atheism is so widely misunderstood that it is preferable to use a term without so much baggage.
When it comes to me, I am an atheist. That is certainly not all I am, but I am that. I see no reason to water it down for public consumption.
I do not believe in gods, but I do believe in plenty of other things. I'm not sure I am willing to allow continued religious privilege. I'm not sure I'm willing to remain a non-believer. I'm an atheist.