Uuugh, I just finished reading them and, while the first one was pretty good, the second one dragged a bit and the third was interminable! It felt like the author had a laundry list of ideas that he hadn't fit into the story yet, and with the third book was on a mission to cram in every last one. It's something like 2-3 times longer than the first one and by the end I was only reading out of determination to finish it.

There were also a lot of odd assumptions/conclusions about how people would behave but I put that down to a different cultural mindset (and in this sense it was pretty interesting), however some of the recurring social themes stretched credibility a bit. Also for a book that's generally held up as being hard sci-fi, the actual science aspect had some glaring flaws in pivotal events which really strained belief. (Well, either that or my understanding of astrophysics is way off...)