I've believed for a long time that Amazon couldn't possibly stick with what is clearly an inferior format (Mobi). Mobi vs EPUB is like Mosaic vs Firefox 4. There is simply no comparison.
And lately there have been more and more clues that something is shifting.
A few weeks ago, Overdrive said that they would be supporting Kindles and most importantly, that libraries wouldn't have to buy new files. Indeed, their "existing collection of downloadable eBooks will be available to Kindle customers" and "work for existing copies and units".
Most everyone pooh-poohed the EPUB angle and said that it didn't mean that Amazon would support EPUB. In particular, they said that Amazon wouldn't want to leave behind its legacy readers... the Kindle 1 and 2, and all of the customers who already use those readers. Instead, they said Kindle would simply convert the EPUB files on the fly to Mobi, and then display the Mobi formatted ebooks. They said that Amazon has been accepting EPUB files from publishers for years and converting them.
Then yesterday (was it only yesterday?), there was a post on what I fear now is a pretty questionable blog, that claims that “soon the Kindle ereader will have the full capability to read ePub books”. Much of the wording in the article was almost intentionally ambiguous, and didn't necessarily rule out Amazon continuing to convert EPUB files to Mobi. But the post still generated enormous interest and discussion.
And then today, I found a comment to one of the discussions about whether or not Amazon would truly support EPUB (without conversion to MOBI) that mentioned that the Kindle Previewer has been able to open EPUB files since September.
I downloaded Kindle Previewer (again) and opened up my new Audio and Video in EPUB miniguide. (Sorry, had to get that in there :). Kindle Previewer converted my EPUB file to Mobi in a few seconds. It didn't look amazing, but it was readable. And the videos played:
Now why would Amazon want its Kindle Previewer to be able to read EPUB files, albeit in a simplified way? It's because of the legacy readers. If a Kindle can convert EPUB to Mobi on the fly, that means all of those older Kindles are still viable (if barely). And all of those customers are still happy.
More importantly, it means that new Kindles can embrace EPUB whole-heartedly. Perhaps on a new color tablet. (With Mobi? I don't think so.) With audio and video. With all the interactivity that seems imminent with EPUB3.
Again, let's look at what happened on the web. Browser developers wanted to upgrade their offerings without leaving legacy websites behind. They figured out ways of reading those old sites while embracing all the new features available in succeeding versions of both HTML and CSS. Some of those systems were more successful than others, but not a single one said, "No, we can only support HTML 3.2 because that's what our users' websites were written in."
Publishers want the control over what their books are going to look like. They don't want to depend on KindleGen. And they want the features, call them bells and whistles if you must, available in EPUB.
I believe that Amazon's strategy is to convert EPUB to Mobi for legacy Kindles and support real EPUB in the next Kindle. I could be wrong, but I don't think I am.
P.S. Do I have a horse in the race? Sure. I wrote a book about EPUB. But I wrote the book because I think EPUB is awesome. I love that people can publish their own beautiful ebooks with audio and video with little more than HTML and CSS. I love it that you can tinker with the code. I love that EPUB is growing and changing and adapting. Sure, I want Amazon to support EPUB, but I also think it's the logical thing to do.