The third edition of this established textbook has been thoroughly updated and revised. It maintains its broad coverage of topics from phonetics to language variation, and increases its accessibility by incorporating a more descriptive, less theoretical approach.
Excellent & pretty approachable - she explains every linguistics concept referenced so I think you could go in knowing nothing about linguistics and understand it well. Learned so many cool things about Japanese from this, and was also a great overview of the basics of how Japanese works. I guess the one downside would be that it doesn't go fully in-depth on some subjects; for example, she doesn't go over every verb form. But I think that's kind of to be expected since this isn't intended to be comprehensive.
I wish I had read this book while I was studying Japanese. While it is hardly intended to be a supplementary textbook to a language class, I found that many of its topics clarified gaps and longstanding questions that I've had about Japanese. I also found this book fairly approachable for my background with only minor linguistic training, and I think it would still be comprehensible and interesting for someone with no linguistic background at all, though some parts could likely be skipped.
Overall, this is an excellent textbook chockfull of information; I did not assign it to my class, but found it useful for data mining. Unfortunately, I disagree strongly with some of the analytical points, and could it not give it a full 5.