What starts out as a grouping of short stories in the first book evolves into one of the greatest space operas of contemporary Sci-Fi. Books two and three are the strongest, and book one is probably the weakest. Even having said that, the entire series is amazing, mind-bending, and essential for Sci-Fi fans.
Like most series, by the time you get to the last book the author has a platform to espouse some personal philosophical or quasi-religious BS. The final book in the Hyperion Cantos is not dissimilar in this regard, but is still a great read and a strong finish.