Should I state the obvious that, when you're looking for textbooks, it's important to choose a reputable publisher? They're suppose to catch stuff like this.
A decent number of the non-self-published ones seem to come from Course Technology PTR, which is moderately respectable. They do have something of a reputation for not being too rigorous or selective, but until now I hadn't thought of them as having a bad reputation, just a bit of a shamelessly commercial one. They rush out large numbers of textbooks on recent technologies, of mixed quality, but some are good. Apparently their reviewing could use some improvement, though.
On a recent contract for writing e-learning materials I had an editor who was herself a subject expert going over the words, references and the actual pedagogic design. Then I had the multimedia team suggesting changes and sequencing the material.
I'd say the original writing was 40% and the response to editing was 60%.
PS have a look at the image they used on the top of the article... I've got an embarrassingly large number of those books...
Hmm, interesting. That level of detail is fairly uncommon for academic publishing from what I know, though I am not too experienced myself. When someone like MIT Press publishes a book, the way I've heard the process described is that three external academic reviewers will give high-level feedback and make publish/don't-publish recommendations, and then one MIT Press editor not necessarily expert in the area will do layout/stylistic/copy/flow editing. But partly that's because they have a line to walk between providing real editing and quality control, but also providing a not-too-filtered platform for authors to put out their own views.
I would hope that extensive plagiarism would be caught by one of the academic reviewers, though.
Though with Course PTR it's probably more just lack of per-book resources. When you're rushing to get out a book that amounts to a manual for XNA 3.1, and you put out dozens of those books a year, there's only so much detailed editing you can give it.
