Search and Book-Content Discoverability

Related to my recent aside about my first "organic" GBS result is this recent and relevant item from Michael Jensen over on Publishing Frontier (the bold emphasis is mine):

I’m still convinced that for small-market publications in particular — the kinds of books that are generally hard to justify significant promotion of — openly indexable content is a precondition for survival, in terms of long-tail backlist success in the scholarly environment. People find something, link to it, and thus promote it for free, for us, in the venues that care about that publication.