As a senior/preaching pastor, I may have read more books on preaching than perhaps any other subject. Of all I've read, MacArthur's is the very best for moving from exegesis to exposition. Other books are better on oratory method (e.g., hold your hands this way when you speak, make eye contact, etc.) but no book I've read does a better job of teaching you how to take a bare passage of Scripture, examine and interpret it properly, and then turn it into a sermon. I highly recommend this volume to all preachers - probably more so than those that teach oratory method. You can ususally figure that sort of stuff out on your own.
The book gave some helps on how to improve your preaching; but for the most part it tended to make the reader feel inadequate and not up to the challenge. I was disappointed, most of JM's books are excellent. after reading the book I came away feeling that no one would be qualified to be a preacher by his standards.