Other reviews have discussed the content of this book and discussed Tony Campolo. I would just like to mention a few things:
This book does not rehash Dr. Campolo's much earlier Christian current-issues book, 20 Hot Potatoes Christians are afraid to touch. The thread constantly running through Speaking My Mind is criticism of the evangelical community. 20 Hot Potatoes is just as valuable, but is a scattershot discussion of issues.
If you don't know what dispensationalism is and why it is important in both evangelical theology and how evangelicals relate to the world, the chapter "Is Evangelicalism Headed For a Split?" will explain. I'm relatively ignorant in theology, so I didn't know what dispensationalism is, and appreciated the information. Dr. Campolo opposes dispensationalist theology. After learning what it is, I can't say I believe in it either.
Both Speaking My Mind and 20 Hot Potatoes trumpet that Dr. Campolo is some sort of rebel (in that he's a politically liberal Christian evangelist, and the most prominent evangelists tend to be conservative), and the jacket of Speaking My Mind even claims the book "one of the biggest risks of Tony Campolo's ministry." He makes too much of his perceived rebel and "radical" status, as though his views will enrage conservative evangelists so that they'll be out to get him. I don't think so.