Horton writes from a conservative Reformed perspective but non-Calvinists will find much to agree with. Horton describes how Gnosticism has crept in (almost taken over, really) much of evangelicalism (including Fundamentalism). Whether you call yourself a Bible-believing fundamentalist, a conservative evangelical, high-church, a liberal or a skeptic you will get much out of this book if you have an open mind (Roman Catholics and Orthodox will probably read this book and say, with some justification, "I told you so").
Much of what Horton says is relevant to the culture wars (including the war over science, although that isn't really a theme of the book). This is one of the most important books I have read in five years. I think sometimes we talk past each other because nowadays things are so confused.
Also, I would like to take this opportunity to apologize for not posting my position in the age of the universe debate in my reply last night. If any are interested, it is posted here.