So far, no one has been able to unseat the Kindle for dominance in the ebook reader market. The Kindle's success is based in part on good design, it has gotten a major boost from Amazon's e-book store, which held 275,000 titles when we surveyed the e-reader market in our last issue—more than twice as many as Sony.

But next year, Barnes & Noble could take a big bite out of Amazon's lead. The retailer announced that it is offering 700,000 titles on a range of platforms, including the iPhone, BlackBerry smartphones, and, perhaps most importantly, the much-anticipated e-reader from Plastic Logic, currently slated for an early 2010 launch. (Though, as I recall, it was formerly slated for an early 2009 launch. The best laid plans ...)

Can Barnes & Noble catch up to Amazon? Amazon will probably boost its library to 700,000 titles or more, quickly obviating any quantitative advantage. After that, it depends in large part on the quality of the Plastic Logic device. The e-book reader market is still in early-adopter-land; I, for one, am sitting on the sidelines until the third generation of devices is released.

Amazon has done an impressive job of building up this market, but it has no iPhone-like hold on its customers—no app store, for example, to keep customers from switching to a new, better device. If a decent competitor comes along, its lead could evaporate quickly.