They are short, around 45 - 60 minutes in length. If you click on the title for each book you can see exactly what is covered on each track and how long each track is. Also, there is one sample for each audiobook.
You might not get the same degree of detail compared to a reading a book on the subject, but getting an overview/general knowleadge about for example J2EE patterns in 1-2 hours which can be obtained while driving to work is pretty neat.
It might be nice to have a diagram , but I guess you can't have it all after all, if you want detail you can always consult a book.
It is difficult to cover technical content in an audio format. I love books and for software developers screen shots and code samples are important. That said, in my experience as a professional developer, I have found it extremely important just to have an awareness of what is out there and a basic conceptual understanding of what it is, the advantages and disadvantages, and when to apply it (this is really what is covered on the J2EE Patterns audiobook). If you know this, then at least you know what to look for and the deeper details, code samples and diagrams required for further consideration or implementation can be found on the Internet or in a book.
Also, many people find listening to audiobooks a great way to help them remember details, which is where a product like our Java Syntax module fits in.
I do not have any grand illusions of our product replacing books (my background is technical, not in marketing!). But, our products are a great complement to what is currently available. One of our listeners found that he picked up valuable knowledge by listening to our modules while out for his daily run. There is no other product which would allow him to do this.
Well done! I'm an instructor who's always looking for additional resources for my students. These are fantastic pre and post course support. I absolutely agree that diagrams and all that are required, but I have many students who've asked about audio books for their commute time etc.