Creator Backlash: Clarke mentions in the Millennial edition that he wrote this when he still had a belief in the paranormal. At least one edition of the book includes the extremely unusual disclaimer "The ideas expressed in this novel are not those of the author".
Technology Marches On: One of the many things that leads to the golden age for humanity is the invention of a process which uses blood to determine who a child's father is. This was futuristic at the time the novel was written and it's compared to fingerprinting. In real life a child's parentage can be determined, but involving DNA instead.
Fake American: With the exception of Colm Meany, Mike Vogel, and Charles Dance who keep their own accents, almost every major role in series is played by an Australian actor due to the series being filmed there.
Irony as She Is Cast: Peretta's main arc is her struggles with her lifelong religious faith in the aftermath of the aliens' arrival, eventually taking her own life due to the loss of her beliefs. Her actress, Yael Stone, is an atheist in real life and has identified as such since childhood, choosing not to even have a Bar Mitzvah ceremony when she turned thirteen.
" is based on/inspired by this novel, as is of course the composition "Childlike Faith In Childhood's End"