This book is downright cuddly, and I mean that in the best possible way. ( )

This is an intensely anecdotal book that relies on untestable unverifiable and unrepeatable "statistics" which seem to indicate the growth of an ecumenical movement. But he is dead-on correct. As he suggests, "Religion is to the 21st century what ideology was to the 20th". {Compare, as ideas (Thesis and Anti-Thesis) are expressed, absorption and co-option (Synthesis) is inevitable.}
He also says things that make very little sense to those of us who are not immersed in the extremely watery (or some would say, speculative) depths of Religion. For example, even the title is stroked: "Tolerance does not put a face on faith". What does that mean?
It appears that he means that the apparently conflicted Religious confessions can tolerate one another. They do not need to go farther, to cohere, or cooperate. However, "tolerance is not enough because it has no educational component". Many faith traditions are exclusive -- "they view themselves as the one true way to salvation".
This collection of reports from across America of "Open Mosque Day" and an annual open house for a Hindu Temple, and surveys showing tripling participation in inter-religious worship, does show a possible "cultural shift". Certainly, from his rich religious background, (professor of religion at Syracuse University, grandchild of Reinhold Niebuhr) the author is showing great leadership and insight.