I’ve said this before. Actually, I said it when sales of Kindle took off. And there’s a reason it wins: Whispersync. MOBI is an ancient and limited/limiting format. EPUB is an evolving and flexible (if not quite limitless yet) format. MOBI was all but dead when Amazon used it for the Kindle, but readers don’t care. They want their ebooks and they want them to be more convenient than paper.
Here’s the problem: Technology gets in the way of reading ebooks. MOBI wins simply because it happens to be the format Amazon used to make it painless for people to get books. (And if you think Barnes & Noble’s nook is going to become the EPUB equivalent of Kindle, you’re kidding yourself.)
Unfortunately, for EPUB readers built on the Adobe Digital Editions developer kit, those illustrations won’t scale. But they do in Overdrive, Kobo, and iBooks. Imagine that. So I had to manipulate the images down to the smallest size that was still barely readable, because most people read EPUB on ADE-based readers. (I use Bluefire in iPad.)
MOBI, on the other hand, that ancient and limited/limiting format, scales the images and while they’re still small on the Kindle, you can read them and they do zoom a tad. You can argue that it’s a reading software problem, and not a format problem (why blame EPUB? you wail), but it’s really irrelevant.
In this equation, the person who bought the book is the only person who matters.
No format does what it really needs to do to replicate the convenience of the print reading experience. All you have to do to read a print book is know how to read.
This format bullshit isn’t like having mismatching books on a book shelf. This is like having print books you can only read if you have a GE 75-watt bulb in your 60-watt lamp that has to plug into a European outlet. In the United States.