From a fundamentalists perspective this book is 20% garbage and 80% gold. Too many of us are attempting evangelism by using methods that are not really producing fruit and our congregations are growing old and withering. Or, let's be honest, we are not evangelizing at all. I was so thankful to read a book by someone who was saying exactly what I had been thinking/feeling for quite some time.
That said, the 20% that is garbage is disturbing. The evangelism values that Mittelberg commends are fairly well presented except the one on cultural relevance. Mittelberg totally misrepresents 1 Corinthians 9. Moreover, he fails to see that sometimes achieving "cultural relevance" demands a lowering of our Biblically held positions. There is nothing more relevant than God's Word as it is properly exegeted and applied to the life. God is not glorified by evangelism that is fought with carnal weapons! I would recommend this book but with this caveat. Read Dr. David Beale's book: Pursuit of Purity along with it.
Matt
Although there are shorter and perhaps more exciting books on the topic of evangalism, "Building a Contagious Church" is at the top of my list. Whenever possible, I research the background of the writer/s when reading a book to be sure that I can count on the information they are sharing. Willow Creek is doing many things right and it shows! This book is a very good start for those who have churches that are becoming too inward focused and isolated. Start reading today and be inspired!