There is a simple way to decide whether one is an atheist or secular humanist. If you think the world would be a better place without religion, you are a secular humanist. You may call yourself just an atheist, but you are not. You have gone beyond a non belief in deities to a set of arguably cultish beliefs.
Leaving aside his claim of Secular Humanism being a cult, that differentiation is quite interesting.
I am a secular humanist, and I wish everyone else was too. Intellectually I understand the position that someone who believes in the supernatural cannot be trusted to make sound moral decisions in complex situations. The fact that there is even a stem-cell debate is evidence of this.
We are all aware of the ill-effects of religious belief, but there are also benefits. Is society on the whole better off without such superstition? Are we overestimating the rational capacity of humans?
I have personally witnessed someone very close to me seeking solace in religion when her child was seriously ill. Without her belief she would not have had the continual strength and hope to battle on through the great many hardships that were presented to her. Having seen such evidence of the benefits of faith, it is rather difficult for me to indulge myself in the righteous zeal of the Anti-Theists.