Here is the book that my college used in teaching Japanese.
Amazon product ASIN 0300038348If you look inside the book, notice how the Japanese is purely written in romaji. The reason for this is that the author of this book, Eleanor Jorden believed that reading and listening are instrinsically linked together, as reading and writing are, respectively. However, since the link between speaking/listening and reading/writing are much more tenuous, it is favorable to the student to separate these fields when learning Japanese. The theory goes that by using romaji, one can learn to speak and listen to Japanese at an exponentially faster rate from the beginning than if one were forced to learn to read Japanese first.
Although I do believe that Jorden is correct in her assertion that one can learn to speak and listen to Japanese independent from reading and writing, and doing so creates an environment where the beginning student can pick up more of the language at a quicker rate by this method, the usage of romaji throughout her books creates a depency on romaji that is difficult to break.
Not only that, but since the written Japanese is handled completely separately, it does not reinforce the language material from the spoken books much at all.
Also, the written language books use much simpler Japanese than the spoken books for obvious reasons, but the result is a huge gap in one's speaking competency and one's writing/reading competency.