The astonishing thing about the transformation of print into digital distribution is not that it has taken so long to finally happen but that, once begun, it is evolving so rapidly. A year ago, digital readers were barely taken seriously. Today everyone from authors to readers assumes we will see a massive step forward in technology in the next few months.

Time magazine estimates the number of Kindles sold so far at 1.7 million and quotes Forrester Research’s prediction that the number will reach 3 million by the end of the year, as Amazon (AMZN) surfs through 1 million Kindle units sold in the holiday season. A price cut and the introduction of a new international edition sure won’t hurt, nor does Forrester’s expectation that sales will double in 2010, to 6 million.

All that for what remains a pretty crappy device. So the question about the digital reader market isn’t whether the devices will improve but by how much they’ll improve, how fast, and who will offer the next innovation.

On the content side, the Frankfurt Book Fair turned into a series of rolling press conferences as digital publishing initiatives were announced, the most significant one coming from HarperCollins’ former CEO Jane Friedman, who launched an enterprise that puts e-books at the center of its business plan. That’s exactly what the e-book business needs—and dozens more like it.

Still, the hardware’s got a ways to go. Barnes & Noble has scheduled an event for Oct. 20 at which it's expected to announce its own proprietary device that may hit stores as early as November to pull in Christmas sales.

Rumors had Barnes & Noble (BKS) taking a big step forward by using Google (GOOG)’s Android operating system to streamline the device’s connection to a wireless service. This idea was floated by Gizmodo and it makes a huge amount of sense. But the tech site’s subsequent posting of images of the Athena—that seems to be the name of the B&N device—reveal the clever use of an LED screen to navigate one’s library. That’s a start but hardly what users of the device would like to see from Android.