This post on the popularity self-publication reminded me of yet another argument towards the survival of the book that didn't seem to have been brought up in any of the Forbes articles: namely, that having a physical published book out in the 'real world' still seems to be the holy grail as far as writing goes, even for those who have gained mass followings from putting their works online. Example: Movies in Fifteen Minutes, a set of parodies that were initially put up by the author on her livejournal for the sake of simple entertainment. Eventually she was contacted by a publisher, and has now published a book - the text of which is, interestingly, not available online. The author still posts free parodies, but only for movies that she's fairly sure she won't be including in future books.
There are a couple other 'rags to riches' stories of unknown writers garnering book deals through their online fanbase. What I find interesting is that these authors hardly ever join the trend of posting the text of their published works online except in the typical form of snippets for advertising purposes.
Obviously, this bodes well for the survival of the book - it seems clear that the dream of seeing your name on the spine of a hardback in the bookstore remains the same. On the other hand, if the future really does lie in the interaction between html and the printed page, one would think that those who got their start from the web would be the most eager to embrace that change instead of buying right back to the same system.
Then again, I know that if anything I wrote and posted online ever attracted a publisher's attention, I'd dive happily into the traditional system, copyright deals and all, headfirst - so obviously I'm not in any position to judge.