Atheism is more than merely not believing in God.
It is not as if you had never encountered the <God>
meme -- you have, and you've decided, for various
reasons, whose validity is presently irrelevant, to
reject it. Those reasons, and the behavioural
effects of viewing yourself as an atheist, most
certainly constitute a meme-complex.
Agnosticism is the refusal to host either pro- or
anti-God memes -- but even agnosticism is a meme.
-- Robin