there is no essential difference, only an agnostic or theist would tell you something like that. I'd recommend you avoid categorizing yourself in either way as often as possible, but when you have to commit to something, claim to be an atheist, its a much richer tradition (filled with fewer pussies =D ). Instead, however, I'd recommend you generally and philosophically consider yourself an Ironist. I'm an Ironist, the tenets are simple, there is no such thing as an essential or universal truth when it comes to anything. The benefits of this kind of thinking will help to keep you from awkwardly investing yourself into topical trash on an emotional level. You never see me get all tense and up set by the things said on this forum. The reason is that I value hearing and exploring all potential explanations and opinions to everything. Most of them, on this forum especially, are simply retarded, but you do find rare gems. An Ironist can also consider himself ametaphysical. Much in the way an atheist does not think in the context of theism, an ametaphysician does not think in the context of metaphysics, specifically Ironists do not worship the idea that there is some kind of knowable reality. Even in our own idiosyncratic personal truths we are aware of their subjectivity and contextualization, as well as often aware of their contingent origins. That is to say, an Ironist realizes all ideas have a point in origin.

Also, ignore aqua's understanding of an agnostic. Even most agnostics would phrase it a bit more carefully. It isn't that they believe in a possibility of a God, that makes them seem like theists in waiting. They're really people who don't think about God or religion, but because they were born into a culture with people who do believe in those things, they have come to attribute the unknowable to the acceptable. To an agnostic, God is unknowable, the word gnostic specifically referring to knowledge. However, to the same agnostic, there is a confusion between something being unknowable and something being alright to think. They assume that because God is unknown and unprovable that it would be a reasonable step to chose to worship him. Of course, this confusion stems from the fact that most agnostics have to spend their lives placating Christians and not atheists.