image I should have picked up on this yesterday. A CNN story says “more than a quarter million” Kindles have been sold. Whose numbers are most helpful? CNN or Forrester Research, which estimates 400,000?

Now, here’s the fun. Unlike Amazon, Sony is willing to give out sales figures for its Readers—in this case 300,000 globally.

So I’ll next ask a rude question. Let’s say Amazon has moved just 299,999 Kindles or whatever. That would be more than a quarter million. But it would still be fewer than Sony’s official 300,000. I’m just frustrated that CNN doesn’t give a source for the “more than” number. Which analyst or whatever?

Psst! My gut instinct is that Amazon has moved more hardware than Sony. But you never know. Come on, Jeff Bezos. Follow Sony’s example and level with us.

Real winner: The iPhone?

Of course, the real winner going by sheer numbers might be neither the Kindle nor the Sony Reader but rather the iPhone.

Remember, the Stanza reading app for the iPhone has drawn more than 500,000 downloads. Add in the stats for eReader and other iPhone-available programs, and it’s clear that there the e-reading world encompasses a lot more than dedicated readers of the Kindle variety. Check out some Wikipeida-published stats for the iPhone and iPod Touch.

Amazon’s ePub challenge: Did it bungle its workflow?

Meanwhile, speaking of the Kindle, another pesky question arises—one that could impact content availability in ePub, and thus hardware sales.

Could technical bungling be why Amazon is so far behind rivals on the ePub issue? Might it have been so eager to crank out the max number of titles for the Kindle that it didn’t think beyond getting them into the DRM-tweaked Mobi format that the K machine uses? Just what kind of workflow are Jeff B. and friends using? Mobi is a primitive format designed originally for use on small handhelds, without ePub’s richness, especially for STM apps. Not to mention other issues. How well will Mobi handle shared annotations, reliable interbook linking and other wrinkles that the ePub world hopefully can enjoy in the future?

Might Amazon end up having to reconvert many or even most of the 200,000 titles now it Kindle format? Or more likely will it settle for less than ideal conversion from, say, Mobi, for just about everything?

Yes, I know: the current Mobi Dekstop can do conversion from ePub files. But that’s no substitute for native reading capability, which eReader software will gain in the near future.

If Amazon won’t do ePub…

Luckily, the large publishers can farm out conversion work and come up with workflows that can do justice to ePub. One format expert suggests, for example, that the best core format could be  “DTBook-based ePub or DocBook and similar specialized DTDs” (links added).

Ignore the jargon if you wish. Just keep in mind that a grainy video isn’t going look any better when viewed via HDTV. Same idea here.

Of course, the issue isn’t just the capacities of the format, but also the ability to reposition it for many devices. Hello, Amazon? Given the rise of the iPhone, you’d better start caring. Why, you may even have stopped Mobi itself from haivng an app for the phone, even with the proprietary format in use.

For small publishers, the good news is that Amazon rivals such as Fictionwise will be switching to ePub, and both eReader and Stanza will be able to read it—in fact Stanza does now. eReader is smart enough to know that ePub is the format of the future. I suspect it will even offer nonDRMed ePub books.

Watch out, Amazon (and some publishers). You may think your customers won’t demand DRM-free ownable books in standard formats, but the eventual outcome could be rather different from what you expect.

Related: Can we hope for an Amazon and ePub union?, from Mike Cook at ePub Books.

(Thanks to Sam Hendrix and Hadrien Gardeur for pointers to the CNN story.)