After checking this out from the library 3 or 4 times, I've finally decided to buy it off Amazon. In my experience, it's always something of a risk to trust a book of foreign idioms or slang, because it's difficult to discern which entries are actually useful in everyday conversation and which ones are outdated/bookish/cheesy and will only get you laughed at. After checking out this book for the first time, I decided to ask a native speaker's opinion as to whether the phrases were worth studying, and as he flipped through the pages, his initial expression of skepticism quickly turned to surprise. "There's nothing but useful phrases in here!", he told me. At a few of them, he laughed, saying excitedly "this is a good one! You'll sound like a native if you say this!" I've been studying this book since, and have been able to use as well as recognize the phrases in daily conversation to great effect.
The phrases are listed in English alphabetical order, a page for each, and the heading is written both in romaji and Japanese (with kanji). There is a paragraph explanation on the usage of this phrase, and about 5 example sentences with English translations. These example sentences are very natural, and a good variety of casual spoken Japanese and newspaper-type Japanese. However, these example sentences are all in romaji, which is my only complaint about this book. The only place with Japanese writing is the heading of each page, where the name of the phrase is written.
I would recommend this book for upper-intermediate learners with enough conversational ability to understand the example sentences.