Thanks, that makes more sense. Now I'm curious about that "10,000 year" quote though. I'll try to find it after finishing the book. Perhaps it's supposed to be a quote from the future?
I find the lack of aliens in this series (well, intelligent aliens) interesting. Just off the top of my head, I feel that this stems from the series really being an examination of humanity from an incredibly broad perspective, based on the massive scale of the series. It's funny though, because the introduction of an alien species in such a work could both jeopardize the focus on the "human universe", and yet also shed new light upon it given the right approach. The lack of non-human civilizations, however, also creates a certain lonely atmosphere to the series that's very effective, in that it pushes humanity to face the universe as this indomitable force. It's infinite, merciless, and utterly indifferent, and yet the civilizations seem to be continually finding ways to bind it to their will, yet still always finding the complexity and randomness to subvert them. No matter how great they become (Leto being the prime example at this point), they're never a match for the adversity of existence.
ETA: To sum it up, the series almost feels like the ultimate Man vs Nature.