Doug Hoyte styles Let Over Lambda as a successor to Paul Graham's On Lisp; I think Let Over Lambda comes close but ultimately falls short of that goal.
The best parts of the book are the chapter on read macros and the subsection on sorting networks. Great, practical examples and illustrations of good programming style.
The worst parts of the book are the chapter on implementing a Forth interpreter in Lisp and the "caddar accessor generator."
The chapter on anaphoric macros changed my mind on the topic. It's ok; use them when you need them. The book contains a lot of material on what Hoyte terms sub-lexical scoping - various interesting ways of using macros to capture free variables. This did not strike me as a particularly useful programming technique.
As pointed out in other reviews, the book could have used a lot more proofreading and editing. Hoyte chose to self-publish the book.
I suggest reading Let Over Lambda only after you have read On Lisp. Let Over Lambda is a fun book about some interesting Common Lisp programming techniques, but it could have been shorter.