Reader David Rothman: Actually the $10M figure is rather believable--it's a speck of total book biz sales. Each year Tom Clancy alone may be earning several times the revenue of the whole e-book biz. Why? Partly because of heavy-handed Digitial Rights Management schemes. (I've been advocating e-books for almost a dozen years, and I have yet to pay for a DRM-"protected" book (though I may succumb eventually).
More from David here.