A bit of random speculation about the New BSG:
People have been wondering how to reconcile the "Life Here Began Out There" concept of BSG with the pretty overwhelming biological evidence that life on Earth originated on Earth. Especially with the info that the Exodus from Kobol was only 3000 years ago, when there was very distinctly known civilizations on Earth already.
What if it did in BSG as well?
Say, several centuries from now, Earth is polluted and nearly ruined. An exodus to a newly discovered inhabitable world across the Galaxy begins, with this new world named Kobol. Kobol is the new home of Humans for a long time, centuries or millennia. Eventually, Kobol itself was uninhabitable, so another Exodus was begun, this time to a series of 12 planets discovered further across the Galaxy, with one faction wanting to return to Earth and rebuild the original homeworld. The "Earth" faction loses touch with the rest of the colonies (or even severs ties, disliking them for political or ideological reasons), and the Colonies spend their 3000 years before the Cylon Holocaust. The idea that their civlization is distantly descended from ours makes them having the same road signs and fashions at least a little less strange (even if they are ancient designs, they are known to them).
Now, the Earth faction has had 3 millennia to rebuild Earth, and it's probably somewhere at least after the year 6000 AD to our calendar. When they find Earth, will it have cities like Washington DC as ancient ruins preserved like we look at the crumbling remains of Rome? Will there be an entire alternate Human government there with a a divergent culture or some kind of revival of older Earth beliefs. If the Colonials are polytheistic, maybe the Earth Humans returned to the monotheistic beliefs common to Earth of our epoch, and if the Cylons have any reason to suspect this (they infiltrated the Colonies, maybe information on ancient beliefs of Kobol before the Lords of Kobol were worshipped as gods indicated a monotheistic belief system, hence Boomer's quote of "be fruitful"), thus the great Cylon interest in finding Earth, finding Humans who share their beliefs, and the Cylons attacked trying to force the Prophecy to come true so the Humans would lead them to Earth, where the Cylons hope to find a major addition to their religion?
Wild speculation, but I'm sitting here waiting for my ride to Gen Con to pick me up, and it just went through my head.