You can see the Billboard below, along with my comments. Lowder writes this about President David Silverman:
Silverman seems to have fallen into the trap, typical among so many leaders of organized atheism, of thinking that the United States is a post-theistic society. It's not and it's delusional to think otherwise.
Since the U.S. is not a post-theistic society, what is the point of the ad? It's not like the attendees at the Democratic National Convention are going to say, "Wow, I was going to vote to nominate Obama, but after seeing that American Atheists ad, I guess I had better nominate an atheist instead." Likewise, I don't think this ad is going to have any impact on how nonreligious voters will vote. I think many pragmatic atheists believe that nonreligious voters do not have the luxury of choosing a viable nonreligious candidate for President: most will vote for Romney or Obama.
From a marketing or public relations perspective, it's hard to see how these ads accomplish anything positive for atheism. As far as I can tell, all they do is create the impression that atheists are rude. Link