eBooks and eReaders are still relatively new, but they've had a major impact on literature. What impact has eBooks and eReaders had on the production of literature (specifically books)?
There are quite a few ways to approach and answer this question:
Ebooks and e-readers are still relatively new, but have shown already that there's a future for them. Even stronger, they're already passing sales of regular books. There are several reasons for this, some of them are: easier to pack several books with you for a trip, ebooks are quite often cheaper or sometimes even free *, they can be read on several devices (phone, pc, e-reader, iPad, ...), ...
Production costs are much lower for an ebook. Most work to get to the ebook is already done as part of the preparation of printing on real paper. So nowadays there's no reason to go for a printed version and ignore the ebook version.
Some claim that ebooks are greener, because no trees have to be cut. But what about the production and energy costs of e-readers, or your pc? If you want to know more about which is greener, go read here.
Authors can release a book much easier. It also gives people the chance to release a paper, a collection of (quality) blog posts, some poems, ... to the wide public. Ebooks don't have to be 300+ pages to be of high quality and useful.
It's still to early to say what impact they'll have on book stores and libraries, but overall they had a quite positive impact on literature.
*I won't go to deep in the discussion on pricing of ebooks. You can claim that some providers like Amazon are asking way to much for an ebook (sometimes even more than the printed version), but this would bring us to far off topic.
Frankly, I read a lot more of what I would term "Literature" than I ever used to, simply because large chunks of it are in the public domain. Given the amount I read, "free" is a powerful motivator.
That being said, I absolutely refuse to pay for ebooks. I work in the publishing industry, and the claims that the costs of the physical product being equal or nearly equal to the cost of the digital product are a sick joke (The e-edition is basically what they send to the printer, so that work has to be done for both products. The printing and distribution have a massive cost associated, and it keeps going higher due to increasing costs in paper, ink, and gasoline.) Until they fix the pricing, I'm abstaining.
For one, it probably requires the author/editor/publisher to do layout and writing in a way that will suit different formats, besides just print. Images don't always work well on a reader (such as the Kobo) due to size or colour.
Writing with electronic formats in mind enables preview versions of the material, since electronic output is easier to create and distribute than print. Unfortunately, pricing does not always reflect this - sometimes ebooks cost more than their print counterparts!
On the whole, I think ebooks and ereaders make literature more accessible, due to the portability and the ease of finding new things to read. It also makes publishing more accessible since it's possible to output just electronic books without a print version, reducing costs and processes.