By Bill Ray
26th August 2008 13:11 GMT

The humble paper-based book isn't burnt just yet. Amazon is keeping schtum as to how many e-books it has sold, but evidence is mounting that predictions of iPod-grade sales and billion-dollar revenues were a smidge optimistic.

Earlier this month CitiGroup predicted that Amazon would shift 380,000 electronic books during 2008, and would see annual revenue of over a billion by 2010. But it's worth taking a moment to see where those figures came from as Amazon won't release any official figures. The story starts with TechCrunch reporting it had reliable information that Amazon had sold 240,000 Kindles, even suggesting CitiGroup might like to revise their predictions based on this new information.

CitiGroup's Mark Mahaney promptly did exactly that, and the Reg reported those predictions. TechCrunch's figures were, it admits, based on devices shipped from the factory rather than sold to punters, and Amazon has been quick to deny that sales are quite so stellar. Analyst Tim Bueneman spoke to Amazon management last week, and was told that the estimates were not reasonable.

In an emailed advisory he explains that Amazon management "told us the Kindle is definitely selling very well, but they also said the analysts and reporters giving out these extremely high estimates 'did not run them by company'". Given Amazon's zip-lipped policy on sales figures, it's unsurprising that TechCrunch didn't check, and the site is standing by its figures despite the comments from Amazon.