After four years of tightlipped praise and vague press releases, Amazon.com (Nasdaq: AMZN) is ready to shed some more light on its Kindle unit sales.

We're not getting actual numbers, mind you. Amazon also isn't really breaking down its different Kindle product lines beyond an interesting nugget on the success of its Kindle Fire. However, today's press release, claiming that Amazon has sold more than a million Kindles a week in each of the past three weeks, is certainly crisper language than what the e-tail giant has divulged in the past.

A million Kindles cleared in each of the past three holiday shopping weeks -- even if it's lumping the $79 Kindle, $99 Kindle Touch, $149 Kindle Touch 3G, and $199 Kindle Fire in one pot -- is impressive.

Amazon also has some encouraging milestones to discuss specifically about the Kindle Fire that was introduced last month.

"Kindle Fire is the most successful product we've ever launched," Amazon exec Dave Limp is quoted as saying in today's press release. "It's the best-selling product across all of Amazon for 11 straight weeks, we've already sold millions of units, and we're building millions more to meet the high demand."

Limp also goes on to say that Kindle Fire sales have been accelerating in each of the past three weeks.

Nice! Having already sold "millions" means that Amazon has shipped out at least 2 million Kindle Fire devices.

Let's frame this a different way. Market tracker NPD Group stunned tech watchers when its channel checks revealed that there were just 1.2 million tablets -- outside of Apple's (Nasdaq: AAPL) iPad -- sold in this country through the first 10 months of the year. In other words, Amazon has already outsold every other non-Apple tablet maker combined. It still has a long way to catch up to Apple, of course, but at least now it has to be showing up in Apple's rearview mirror.

Amazon's eating up the low end of the tablet space. Even having pesky Hewlett-Packard (Nasdaq: HPQ) and Research In Motion (Nasdaq: RIMM) kick in with limited-time fire sales of their higher-end tablets at Kindle Fire-like prices isn't slowing the online retailer down.

Why is Amazon suddenly so chatty? Is it that the company finally feels that it has numbers worth sharing the way that Apple routinely does?

I don't think so. If anything, I think you can thank David Streitfeld from The New York Times for this peeled-back curtain. It was his scathing article earlier this week that detailed how the Kindle Fire's shortcomings -- from the lack of external volume buttons and privacy controls to an easily triggered off switch -- are forcing many early adopters to return their entry-level tablets.

Amazon's simply fighting fire with Fire, arguing its side of the story. Not only has it sold millions, but folks are so happy with the original model that it's ordering millions more to meet growing demand.

All we need now is for Amazon to finally give us actual sales metrics when it reports its holiday quarter's results next month. It will make it that much easier to make an apples to Apples comparison.  

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