I just finished this book this morning, I had tears oozing from my eyes for about the last forty five minutes or so of my reading.
Not a great deal of action in this book, it is a long way from being a space opera. As a Dawkinsian atheist at a point in my life where I'm contemplating my own mortality I found it effected me very strongly but did not make a convert to theism. The book brings together a lot of information regarding the fact that our universe could be seen to have been designed by an intelligent entity, some of which I already was aware of and some of which I wasn't and some of which are fictional plot devices designed to further the meme of an intelligently created universe. Since the fiction devices are provided by the aliens it's fairly easy to keep which is which straight.
Spoiler Warning, the wiki page definitely has some severe spoilers.
http://en.wikipedia.org/wiki/Calculating_GodCalculating God is a 2000 science fiction novel by Robert J. Sawyer. It takes place in the present day and describes the arrival on Earth of sentient aliens. The bulk of the novel covers the many discussions and arguments on this topic, as well as about the nature of belief, religion, and science. Calculating God received nominations for both the Hugo and John W. Campbell Memorial Awards in 2001