I find most of the atheists I know to be either very sophomoric, or anti social. A few are normal...but I haven't met one who smiles very much.
I do so "I don't know". I don't claim to know all of the answers. I do however dismiss any belief systems that do claim to know all of the answers, in the most dishonest and unfalsifiable ways imaginable.
An agnostic atheist.... I am very open to the possibility of a higher power. I actually kind of like the idea of a higher power of some sort, however I haven't seen any evidence to commit me to the idea.