I plan to require this book in the undergraduate typography class I teach, but because it is accessible even to a novice, I'd recommend it to anyone with an interest in type. One of the strengths of the book is its succinctness, but that may be one flaw as well. When a book is so well done, you want more... (Fortunately there is a website which does have supporting materials for those who want more.) Also if you want a meaty book on the specifics of type, then you should also get Robert Bringhurst's phenomenal book "The Elements of Typographic Style." It pairs so well with the overview and examples from Lupton's book.
It is a terrific value and well-produced.