Have you noticed that the price margin between print books and ebooks is narrowing? Not long ago, a reader would have the choice of either purchasing a $14.99 trade version of a book, or pay $4.99 for the ebook version of the very same title. What that did for ebooks was great, but what it did for print books meant they were second choice more often than not, because when it came down to clicking "Buy Now," readers saw the price difference as a no brainier, and they'd buy the electronic version, which told publishers that unless the reader just had to have the print version, the ebook version was good enough.
But, publishers realized that enough was enough when print books were not moving, and more and more books remained boxed up, waiting to be sold, standing in line behind their electronic counterparts. Print-on-demand helped out, but still, the production cost of printing a book remained significantly higher, and publishers realized they couldn't cut print prices because the profit margin was too narrow as it was.
And so, the answer has been to simply raise the price of the ebook, and narrow the gap so that readers would see a choice between a $14.99 print version, and an $11.99 ebook version, and hopefully decide that the print version was well worth $3.00 more.
So ebooks are going up in price, and I see that as a good thing for publishers and authors, yet perhaps not so good for readers in some cases. Some have a limit on how much they'll pay for an ebook, and are very firm in not going beyond that, but if it's a book they really want, they will. We (publishers and authors) are subtly encouraging readers to think twice before making that final decision as to which version to buy, and go beyond their preference as far as format. The book format price playing-field has been strategically planned to level out. And, I think it's working!
So don't be afraid to charge a little more for your ebook. Just don't tell your readers that I told you, lol!