Yes, it's still a belief, lily, but one based on evidence rather than faith. There's a thread somewhere on GN (I think!) where someone posted a list, or a link to a list, of what atheists believe. Being an atheist doesn't mean you have no beliefs, only that you have no beliefs about gods – well, one believes that there are stories and myths about gods, obviously, because there's plenty of evidence for that
, but one believes that the stories are fiction rather than truth... until, should it ever happen, evidence corroborates the stories, in which case, one has reason to believe them, based on the evidence. It's very simple really to be an atheist. You look at the reasons for believing something, or not, and base your beliefs on that. If the evidence changes, your belief changes too. Works the same way as science, which, whatever you may hear to the contrary, is never totally 'settled', but simply improves with time, and more evidence.