Paul Carr is wrong-headed in some places here, just plain wrong in others and generally snide and snarky for little reason (nothing new there I suppose). For all that he makes some valid points.
For all of the reasons above, there are really only two types of person for whom it makes a jot of sense to tear up their book deal and abandon the professionalism, billion-dollar print market, and immeasurable cachet of traditional publishing. The first is highly skilled self-promoter likes Godin who have successfully identified their entire (niche) audience and who know they will only ever sell a certain number of copies of their books to that same audience. Marketers like Godin tend to make the bulk of their money with speaking gigs anyway – books are just a throwaway promotional tool, full of ideas that even they admit will be out of date by this time next week. Might as well take the money and keep running.
The second type of person is more tragic: authors who, for whatever reason, fear they’re about to be dumped by their publisher (or at best paid a tiny advance for their next book) and who want to save face by using innovation as an excuse.