Reuters (NYSE:TRI) has become the latest financial news source to rip into Amazon.com (NASDAQ:AMZN) for its refusal to put up hard sales data for its Kindle e-book reader.

"Amazon could pay for Kindle sales coyness," reads the weekend headline, and I couldn't agree more.

I've been saying the same thing for two years, especially given how Amazon is usually not quiet about its successes. The leading online retailer once set up a digital counter to publicly track how many of Scholastic's (NASDAQ:SCHL) Harry Potter books it was selling. There was also the Delight-o-meter that spelled out sales several holiday seasons ago.

But Amazon has recently been quick to touch up supply-chain problems as demand-side successes. It also recently proclaimed that November was the best month ever for Kindle sales, that December went on to replace November as the best month ever, and that the company sold more Kindle books than physical books on Christmas Day, for the first time ever -- but these press releases are sorely incomplete. I could tell you that I just broke my own personal record for holding by breath underwater, but unless you have some hard metrics of previous breathless dives, you're not going to have my lungs bronzed and sent off to the Smithsonian.

Of course the Kindle is selling well. Amazon has been promoting the device on its landing page since its launch in November 2007. It was also helped this holiday season by supply shortages for Barnes & Noble's (NYSE:BKS) Nook and a lack of buzz for Sony's (NYSE:SNE) Reader.

However, third-party researchers are giving the real number a shot, and it's not likely to be embarrassingly low. Reuters leans on Forrester Research estimates, which suggest that 2.5 million Kindles have been sold since hitting the market, good enough to give Amazon a thick 55% of the stateside market.

Investors want to know the truth, but so do Kindle owners. There's more than a good chance that Apple (NASDAQ:AAPL) will announce a tablet computer later this month. It may be the Swiss Army knife of lifestyle computing that renders one-trick ponies -- like e-book readers -- obsolete. If Amazon doesn't find a way to bond its Kindle community together, and show the world that the Kindle is a mainstream success, it will crumble at the first sight of a potentially superior mousetrap.

If not, it's only going to force Kindle owners and Amazon.com investors to abandon ship when early February rolls around without a press release promoting January as the best month ever.

Is the Kindle really susceptible to a tablet computer? Share your thoughts in the comment box below.

Apple and Amazon.com are Motley Fool Stock Advisor selections. Try any of our Foolish newsletter services, free for 30 days.

Longtime Fool contributor Rick Munarriz has been shopping online for about as long as Amazon.com has been in business. He owns a Kindle, but he doesn't own shares in any of the companies in this story. Rick is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.