An exception... (Score 1)

A single very well-selling and very well-liked e-"book" comes to mind.

God's Debris by Dilbert author Scott Adams has apparently sold like bread. It's the only e-book I've ever invested in, and will probably remain that way for a long time... at least until Mr. Adams writes something else that is exclusively published on the web :-).

Aside from the huge instant publicity it got by being featured on the front page of Dilbert.com, one catch is probably that it's very short, and therefore not a cumbersome read on-screen. Given the drawbacks of current e-book technology (or the means of reading them on screen), the novella format may just be the only feasible form of e-text until one of the ultrathin paper-like text presentation platforms currently in development become widely available. I know I couldn't be bothered to read anything significantly longer than G's D on my screen. Printing out a novel isn't exactly my cup of tea either :-).