I finished the 900 page work last night. The second part takes place through the dreams of a "cybrid" or a cybernetic hybrid (like a terminator but with all human tissue except a data uplink to the AI "headquarters").
The conclusion was satisfying to say the least. I liked how the author explored the relationship and varying degrees of symbiosis between machine and man. Just when you start to think that mankind is completely enslaved to the AIs, dependent for transportation and data transfer at faster-than-light rates, the whole story kind of gets flipped on its head.
I also liked how the AI's camp was not unified, there were different factions. Some wanted to continue the relationship with mankind (some of these were apparently formed during this present information age) and some wanted to obliterate mankind. In the middle there was a third camp, the Stables, that mediated and took a wait-and-see approach.
As kind of a spoiler, the Artificial Intelligences are left to their own devises after being granted independence from mankind. This leaves them searching for a way to perfect Artificial Intelligence, to make a "god" machine. Apparently they succeed far into the future; they built a machine that uses quasars for energy with unlimited computation potential, and this Ultimate Intelligence reports back through time. At the same time the machine "god" finds out that there is indeed a god of mankind. Of course, it follows that the machine god would seek to destroy the god of mankind.
At the conclusion they end up at a kind of stalemate, probably as a springboard into the other three works by the author. Good read if you have the time; definitely worth it.