I’m watching the Kindle for several reasons. First, I own one, I use it and I like it. Second, it’s an interesting new venture: a big, powerful company moving into a new but contiguous market. Third, it’s an interesting product category: the e-reader. I’ve been interested in that idea for years, but it hasn’t (until now, maybe) been successful. Ebooks and ebook readers make sense to me. But why had they all failed, at least until this one?

Interesting data from Tech Crunch last week in We Know How Many Kindles Amazon Has Sold: 240,000:

The Kindle is such a small part of Amazon’s overall business that the company does not break out how many it’s sold. But we found out anyway: 240,000 Kindles have been shipped since November, according to a source with direct knowledge of the numbers.

Doing a little back-of-the-envelope math, that brings total sales of the device so far to between $86 million and $96 million (the price of the device was reduced to $360 from $400 last May). Then add the amounts spent on digital books, newspapers and blogs purchased to read on the device, and you get a business that has easily brought in [more than] $100 million so far. (Each $25 worth of digital reading material purchased per Kindle adds $6 million in total revenues).

Peter Kafka at Silicon Valley Insider adds, in Amazon May Have Actually Sold a Bunch of Kindles:

That number is more or less in line with Citi analyst Mark Mahaney’s estimates from May; Mark thinks the Kindle could be a $750 million business that accounts for 3 percent of Amazon’s sales by 2010. And by our thinking, it compares very nicely to Apple’s iPod introduction: Apple sold 376,000 units in the first year after introducing the MP3 player, in 2001. And the iPod, recall, didn’t require users to actually go out and purchase any music in order to use it–you could load up with music you already had bought, or had stolen. We’ve been skeptical about the Kindle’s prospects to date, but if these numbers prove out, we’ll be happy to reassess.

Interesting. So the Kindle makes it, while the ebook rocket, the Sony ebook reader and some other attempts didn’t. Were the others simply ahead of their time? Or maybe Amazon added a secret ingredient, like critical mass and market power? I’m not sure, and I don’t know that anybody can really be sure, but it’s bringing up some good questions to ask.

Tim BerryTim Berry

Tim Berry is the founder and chairman of Palo Alto Software and Bplans.com. Follow him on Twitter @Timberry.