Gave this to new grads in my office who started working right out of college. The reason I picked this is because the content was basic and did not require any prior knowledge of excel. By the end of going through this book, the person got the hang of excel which was the whole purpose of the exercise.
If you already work with excel, then this book is probably not for you. I will suggest it for beginners. (I work with excel on a daily basis constructing complicated financial models, so my definition of basic might be a bit high, but you can judge the level of this book by using the free previews). Intermediate and advanced users can probably still pick up a few new tricks from this book.