The word 'meme' is uniquely powerful in that it can describe anything from highbrow political concepts to lowbrow internet memes. I find it funny that most people (on the internet) are aware of both memes and Richard Dawkins, but are unaware of their connection. Anyway, the word 'meme' also reduces all ideas to a level playing field. In the world of memes, Marxism and LOLcats are on equal ground. Unfortunately, given just that qualification, all other ideas are equal, including atheism, religions and even worse ideas. So, on to my main point, I think that the reason why religion can be so attractive (as a meme) is that it provides a comforting pantheon of ideas which reward the believer for believing. Atheism, taken at its average form, does not have quite the ability to comfort that religions do.
I propose that we atheists find a common dream for the future and a common goal for our society. Christians dream of a world converted 100% to their belief system, even though they expect the world to end before then. On the other hand, atheists don't necessarily want the entire world to convert, and I would personally discourage any form of atheistic proselytization. I think that our end goal should be a world in which reason rules the public space. People can believe whatever myths they like, but they would know better than to bring those myths to work, to school or to the senate floor. Rational decision-making is our #1 priority. Critical Thinking is the key to rationality.
Given this, I would argue that atheism as a 'movement' should focus on education and education alone. Right now, we're not making as many friends as we would hope with our bus campaigns and other advertisements. Surveys say that people don't trust us, but I don't care. Not trusting a stereotype doesn't matter. One on one, humans are fairly reasonable. It's the crowd that makes us intolerant. As atheists, presenting a united front of 'Atheism" is only going to reinforce the stereotype that we are a culture destroying, godless force of evil. Instead, if we focus more on ensuring that children learn useful mental tools like critical thinking, I think that ( a ) we will have an easier time of "flying under the radar," and ( b ) we will find more allies than we have now. I'm not saying that we aren't already doing this, but I think that funds currently devoted to advertising would be more usefully spent on advocating education reform.
If Critical Thinking becomes a more widespread talent, atheism will naturally become more common. At that point, we can just say "OOPS! Who could have seen that coming?"