With "Battlestar Galactica" now all but concluded (only "The Plan" remains), it's time to turn attention to the new series set in the same universe. Ostensibly a "prequel" to the more familiar series, this actually tells a particular portion of the backstory in the Galactica canon.
As per the final season of "Battlestar Galactica", artificial life is nothing new to humanity. Cylons were created on Kobol long before the 12 Colonies were founded. But all of the Kobol Cylons ultimately left to become the 13th Tribe, leaving humanity to form the 12 Colonies. Thousands of years passed, at which point the Humans of the 12 Colonies forgot many of the lessons of Kobol and began to progress towards artificial life once again. About 50-60 years before "the Fall", the first Colonial Cylons were born. These would eventually become the Centurions that rebelled in the First Cylon War, which ended when the Final Five survivors of the 13th Tribe arrived and offered the secret of resurrection in exchange for ending the war with Humanity.
"Caprica" is the story of how those first Cylons emerged. Considering that this pilot is set about 58 years before the beginning of "Battlestar Galactica", there's very little in the way of direct overlap. The series centers on two families: the Greystones and the Adamas. The pilot is essentially the story of how Daniel Greystone and Joseph Adama (William's oft-mentioned father) end up creating the first Cylon out of a shared tragedy.
The Cylons are the most obvious connection to the mother series, but there are a number of other touchstones throughout the story that harken to future events. Those undertones are there right from the beginning. Greystone is apparently a computer genius, and has managed to create virtual-reality technology. This has, in short order, spawned an underground set of "virtual clubs", where teens and other young people engage in group sex, drug use, and ultraviolence.
This unrated version of the pilot can easily be cut for broadcast purposes, but it might lose something in the translation. As it is, the club scenes are just barely enough to communicate the extent and popularity of the clubs among disaffected teens (and as with the real world, that is quite the substantial population). They could have gone a lot further, because the point is to deliver a message: this is what lies beneath the civilized veneer.
This ties, however indirectly, into William Adama's speech in the "Battlestar Galactica" mini-series. He asks the crucial question: is Humanity worthy of survival? It's not just a question of who is being judged, but who has decided to do the judging. In this case, that would be the Cylons, and they begin as a digital copy of Daniel Greystone's daughter Zoe.
This is more important than the technological aspects of her transition to Cylon. Zoe is member of a monotheistic terrorist organization, and she sees the behavior in the virtual clubs as the disgusting product of the stagnant polytheistic Colonial society. Her virtual copy retains that moral judgment of Human society, and therefore retains her desire to change things. In essence, this not only explains the genesis of Cylon monotheism, but also serves to explain why their particular brand of monotheism would lead them to revolt and, eventually, genocide.