I didn't know what to think of this book at first, and spent over a year before I actually picked it up to read it. It was surprisingly good. The ending kinda sucked (as with most of Sawyer's books) and, let's face it, the book is written for those who don't believe in God; but it was still an interesting read. I wouldn't have been able to think stuff like this up. BTW, the title is misleading. Nowhere does the book actual "calculate" God. Remember: this is a piece of fiction.
The concept is one we've probably all thought of, and it's great that this book was written. Other than that, however, it was just another book. Far greater than that TV series that was based on it, but still. I'm not regretting having read it, but I'm not about to try to convince everyone to read it, either.