I've only had the time to read the comments which list 5 advantages. Here's my response to these:
1. Atheists can make moral decisions based on the specific context.
Not every religion touts "Thou shalt not lie" as an absolute rule. Even among those that do, many members (and I would say %99.9 or more) do not strictly adhere to it. In other words, they also make the moral decision based on the context.
2. Atheists can experience healthy outrage at the outrageous without fear of questioning God's plan.
Not all religions maintain that there is only one God in control of all things, or that the wishes of all deities work in union. Even within Christianity, arguments arise as to what degree God is omniscient or omnipotent. That being said, I'm not quite sure if he is thinking of the Job story here. Even though the character Job never curses God for all of the bad things, Job does express great anger, and he grieves and mourns. So, yes, there is the fear of questioning God's plan, but that doesn't, at least the way I see it, preclude the expression of healthy outrage. But then, this is perhaps only applicable to those who strictly adhere to that fear, which is what Job was made out to be.
3. Atheist can be friends with everyone without having the thought in the back of their mind that this person's lifestyle may be evil.
I disagree that atheists have such an advantage. There are such people out there that would cause you harm, even if you are an atheist (or even because you are one), and I would say that the author would consider that not good, if not evil.
5. Atheists do not live with the fear of hell.
This is true. Is this an advantage? Also, as before, not all religions have concepts like Heaven and Hell.
7. Atheists raise freethinking children; let them pick a religion, or none.
It's not quite changing religions or converting to atheism, but none of my parents' children belong to the denomination in which we were raised. Heck, we're not even all Protestant anymore. Perhaps one of the most shocking things I've ever heard from my dad was when he encouraged me to convert to Catholicism when I got married. This seems to be another case where the advantage is only enjoyed over those who strictly adhere to their version of religion.
And that's all he had in the comments. I'll respond to the rest of his advantages when I have some more time.