I don't believe the article. The idea that eReader owners consume more than those without readers makes sense. I have no problem believing people who read a lot were first into the eBook market.
The idea these eReader owners are now stressing the book market and putting more demand on authors for content is absurd. Ereaders don't make you read faster (slightly slower I'd say). The article is taking an old pressure artists face and rebasing it into a new techonlogy.
An eReader might not make you read faster, but it let you read more often. This is especially true if your eReader is part of a general purpose device that you normally carry with you.
Another possibility is that eReader users might consider more books than they would have otherwise, due to the ease of getting sample chapters. If you hear about a potentially interesting book and you don't have an eReader you have to remember to check it out next time you are at the bookstore. It's easy to forget about it, especially if you have several books you intended to check out. If you have an eReader, you can ask for a sample chapter right away.
In effect, having an eReader is sort of like being in a bookstore all the time. I am certain I would read more if I lived inside a bookstore.
Do you own an eReader? It's less like living in a bookstore and more like owning a book you need to charge and constantly protect from theft while in public.
The idea these eReader owners are now stressing the book market and putting more demand on authors for content is absurd. Ereaders don't make you read faster (slightly slower I'd say). The article is taking an old pressure artists face and rebasing it into a new techonlogy.