The inevitable march of the e-book continues apace with the news this week that in the US on Amazon.com, sales for e-books have outpaced those of hardback novels and the growth of e-book sales is increasing.

In a statement Amazon US said:

"over the past three months, for every 100 hardcover books Amazon.com has sold, it has sold 143 Kindle books."

At first glance this sounds pretty impressive but this is just marked against hardback books, which are in some cases considerably more expensive than the e-book equivent and the paperback format. I believe that part of this success is due to the increasing reccomended retail price of the average hardback book. When combined with a reduction in the cost to buy an e-reader (at least in the US) with the Nook and Kindle both reduced in price, along with the launch of a little device called an "iPad" which launched 3 months ago (hmm notice a coincidental in the launch date there) - the adoption of the e-reader is undoubtedly becoming more widespread.

It also appears that some of the big companies are now doing their best to promote an e-book culture with Apple's e-book store for the iPad, iBooks having already sold in excess of 2 million books and Google's very own equivelent called Google Editions to be launched very soon (offering only "in-print" books at present).