80%. That's the market share Mike Shatzkin, a well-known consultant in the book publishing industry, is predicting ebooks might garner in two years:

Here's an assumption that is not documentable; it is my own speculation. I think we're going to see a US market that is 80% digital for narrative text reading in the pretty near future: could be as soon as two years from now but almost certainly within five. We have talked about the cycle that leads to that on this blog before: more digital...