The first is a completely secular (and so more objective if also less fantastical) take on the Rapture. A rapture occurs, but not according to any rules various faiths might have for who is taken. For those who are curious, Adam Sandler is raptured. The pope is not. As a result, new religious fanatic groups crop up trying to make sense of the new occurrence, others lose their faith because they were not raptured, and so on.
The joys of the book include the great writing and winning characters, and the exploration of grief and loss (if explorations of grief and loss can be joyous). I found the conclusion less tight than the middle of the novel, but all in all it's worth reading.
Rauschenbusch's is a classic I never got around to reading, a book I thought I would be assigned in seminary but never was. In some ways, this new edition of the book is like a brief seminary class, because each chapter includes a short evaluative essay at the end by theological luminaries like Stanley Hauerwas, Joan Chittester, Cornel West, Jim Wallis, Richard Rorty, James Forbes, etc. Perhaps Hauerwas summarizes the impact of Rauschenbusch's book best when he says that after Rauschenbusch, there is no gospel that is not "social gospel." The impact of his thought is far-reaching, if also not fully realized.